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Morphological (Figs. 3–5) and physiological (Fig. 2) data from several crustacean species kept at 19–21 °C show that isolated stumps of motor axons often survive intact for 150–250 days whereas sensory axonal segments usually degenerate within 20 days. Axonal segments of both motor and sensory axons that remain connected to their cell body generally remain functionally and morphologically normal after lesioning. No evidence was found for collateral innervation of denervated muscles from intact motor neurons supplying nearby muscle masses, although the motor nerve terminals may not have completely degenerated. Evidence is presented that motor axons specifically re-innervate their original muscle mass if such re-innervation occurs within 90 days after lesioning. Regenerating sensory and motor fibers make appropriate CNS and peripheral connections so as to re-establish correctly a peripheral reflex (Fig. 2C) found in intact animals (Wilson and Davis, 1965).

The evaluation of the nutritional status of children by means of the various indexes of nutrition, particularly by weight-height tables, has been found to be unsatisfactory (Dublin and Gebhart1). These standard tables are based on measurement of large numbers of children at given age levels and in America include children of different racial inheritances as well as those from various economic levels. From time to time new tables are published, the standards in which are slightly higher than those of previous periods suggesting that the dissemination of the newer knowledge of nutrition is resulting in more nearly physically fit children.2 The inadequacy of these weight-height tables led von Pirquet3 to develop his "pelidisi" chart, a table of nutritional evaluations based on the relation of weight to sitting height: 3 √ 10 × the weight in grams = 100%. Children whose quotients sitting height in centimeters were below 95

Urinary creatine, which in the adult is found only in exceptional cases, for example in inanition, occasionally in women and in certain types of disease in which the catabolic processes are accelerated, is a constant and seemingly normal associate of creatinine in the urine of children up to the age of puberty. Of the various theories advanced in explanation of this, the most generally accepted is that the immature muscle, although producing no more creatine per unit of muscle mass than the adult, has a lower capacity for retaining it. Other theories, with the experimental evidence supporting them, have been thoroughly reviewed by Hunter.1The variation in the amount of creatine excreted in normal children appears to be influenced by a number of factors, for example, the amounts of creatine and of protein ingested, and the periodicity of the food intake which may result in shorter or longer periods

In infants, endogenous uric acid has been shown to be excreted in much larger amounts proportionately than in adults. This appears to be due, in part, at least, to the relatively larger amount of glandular tissue, which comprises nearly one half of the total body substance of the infant. Other factors, for example, the amount of protein ingested and possibly the amount of carbohydrate, which in the adult has been shown to stimulate cellular metabolism, may have some influence. Roughichitch suggested that in the artificially fed infant the excretion of high amounts of uric acid may be the result of the proportionately high intake of protein, although in his recent study he did not find a close relationship between the urinary nitrogen and uric acid.2 Orgler3 believed that the lower output of uric acid of the breast-fed infant is due to the better utilization of the ingested food.

The inference that rickets in the child can be cured by exposure to the elements, particularly of the seashore and high altitudes, is far from being of recent date; but it is to the observations of Huldschinsky,1 in 1919, that we owe the definite incontestible laboratory demonstration that it is light which is the specific curative agent. As a result, heliotherapy or, more specifically, actinotherapy, is gaining for itself a position in the physician's armamentarium that should have been its own long ago.Hand in hand with the recognition of light as an important therapeutic agent there has developed a growing conviction that cod liver oil represents a remedial agent of such efficacy in the treatment of rickets that it, too, was credited with being a specific in the treatment of this disease. As a matter of fact, cod liver oil has been used almost from time immemorial by

Recent work of Folin and Lyman1 points to the conclusion that gout is caused by an accumulation of uric acid in the blood with a subsequent deposition of this in an insoluble form in the various tissues of the body, particularly in the joints and synovial membranes. The retention and consequent accumulation is due to a deficient and restricted power of the kidneys. By means of the new colorimetric method of Folin and Denis2 these investigators have analyzed the blood from a large number of patients suffering from gout and have found the uric acid content higher than in normal individuals; in these patients the blood was frequently found to have reached the saturation point for this compound, namely, 4 mg. in 100 c.c. of blood. Atophan (2-phenylquinolin-4-carbonic acid) caused a decrease in the amount of uric acid in the blood and a corresponding increase in

The dictum "a quart of milk a day for every child" is largely the result of an investigation by Sherman and Hawley1 in which it was shown that the optimum amount of calcium is retained only when approximately 1 quart of milk is included in the diet. Calcium from other sources was found to be less available, lower amounts being retained when the calcium was supplied more largely from vegetables and fruits. The variations in the retentions of calcium of children who were living under comparable conditions as well as the results reported in more recent studies with both children and adults2 suggest that the difference in the amounts of calcium retained may be due in part to the lack of uniformity in the physiologic condition of the persons studied. For example, the potentialities of growth in children or the physiologic balance in adults may have been less

The experimental work involved in this report is the result of an attempt to determine the comparative nutritive efficiency of milk heated to different temperatures. There is considerable evidence in the literature to the effect that scurvy among infants may be caused by feeding cooked milk exclusively; in fact, this notion is so prevalent that many pediatrists still insist on giving raw cow's milk, notwithstanding that the hygienic conditions of this may be far from desirable. It is only in our larger cities that certified milk may be obtained, and even here the price makes it prohibitive for the great majority of homes.In order to meet present conditions and to make milk more nearly safe for infant feeding, the practice of pasteurizing or boiling has been resorted to. Pediatrists differ as to the relative value of these two processes. The European pediatrists1 report excellent results with boiled milk—the

Since the early methods for the determination of creatinine have been replaced by the more accurate quantitative methods of Folin, studies of the excretion of creatinine by infants and young children have become more significant. In contradiction to the previous investigations, which suggested that creatinine is present in the urine of infants only in febrile cases or when meat extract is added to their diet, Funaro,1 by means of these more recent technics, has shown that creatinine is present always in the urine of infants, and that the amount under normal and pathologic conditions does not vary greatly. Further evidence of the excretion of creatinine by infants was presented by Amberg and Rowntree,2 Sedgwick,3 Rose4 and others. The amount of creatinine nitrogen, according to Steudel,5 is approximately 3.25 mg. per kilogram of body weight, whether the feeding consists of human or of cow's milk. The

It is well known by students of animal nutrition that among the lower animals the physical measurements of individuals of a given species can be considerably altered by changes in the amount and kind of the various components of the diet. Whether the norms of growth of the human body can be modified by such means is not known definitely. It seems probable, however, that as more is learned concerning the quantitative biologic needs of the human organism, and this knowledge is incorporated into daily living, the present standards of height and weight may become considerably changed, particularly in regard to children. Undoubtedly, there is a "fairly definite upper limit of body size that is fixed by heredity,"1 but that the present accepted averages are at all indicative of this upper limit is questionable. The physical measurements of the group of intellectually gifted children in California, reported by Baldwin,

Until recently, interest in rickets has been concerned more especially with the rôle of calcium, other elements being considered of secondary importance in the metabolic disturbance. Schabad,1 however, early called attention to the phosphoric acid imbalance, believing that it was a more significant factor than the calcium deficiency. In a comparative study of the relation of the phosphorus of the urine and feces of normal and rachitic infants, he observed that there was a marked increase in the phosphorus of the feces in both breast-fed and artificially fed infants affected by rickets, and a corresponding decrease in the elimination through the kidneys. The normal breast-fed infants under his observation excreted 80 per cent of the ingested phosphorus through the kidney and 19 per cent through the tract; while in his normal infants who were artificially fed, 65 per cent of the ingested phosphorus was eliminated in the urine and

Important as is the subject of urinary acidity expressed in terms of ph, the negative logarithm of the hydrogen-ion concentration, a survey of the literature shows that little work has been done on the urine of infants. In the few cases reported (György1), the determinations were made on mixed twenty-four hour specimens, and in these apparently no special precautions were taken to prevent the loss of carbon dioxid, the importance of which has been pointed out by Marshall.2 Torres3 worked on the titratable acidity of the urine of infants fed different levels of protein; but no ph determinations were made.In some work in our laboratory which included the determination of the total acidity and the ammonia content of infants' urines, it was observed frequently that the freshly voided urine was alkaline in reaction. Further investigations indicated that from time to time there was considerable

The reports of Eddy and Roper1 and Daniels and Byfield2 on the effect of adding substances containing the antineuritic vitamin3 to the diets of artificially fed infants suggests that at least part of the difficulty in feeding these babies is due to a too low concentration of the antineuritic vitamin in many of the feeding mixtures. Cow's milk has been shown to contain less of this vitamin than many other natural foods,4 the amount present being dependent on the vitamin content of the food of the cow, for it appears that "vitamins pass into the milk only as they are present in the diet of the mother."5 When cow's milk is diluted, a necessary procedure in feeding young babies, unless some antineuritic vitamin is added from other sources, too little may be present in the feeding mixtures. The baby who is well and able to

Goat's milk is occasionally urged as a food for infants (1) because a milch goat can be cared for on a small plot of land by the individual family, thereby making available a supply of fresh milk in not too large amounts, and (2) because goat's milk has seemed to be better adapted to infant nutrition than cow's milk.1 However, apart from the generally accepted fact that goat's milk is largely free from Bacillus tuberculosis, there are, so far as we have been able to find, few data showing wherein goat's milk is superior to cow's milk for infant feeding. The composition of milk from a mixed herd compares with that of cow's milk, although among individual goats there may be considerable variation. The casein of goat's milk appears to be the same as that of cow's milk. The relation of casein to lactalbumin in the two milks does

Orange juice has been so universally regarded as an antiscorbutic, that its other possible properties as affecting the well-being of artificially fed infants have not received much consideration. This, perhaps, is to be expected in view of the fact that the daily giving of orange juice is comparatively recent.1 Orange juice has been widely used as a mild cathartic for infants and young children, its potency having been assumed. Recently, Gerstenberger2 has pointed out that there is no experimental basis for this, and states that, on the contrary, orange juice tends to constipate. The diuretic property of orange juice has been noted by Gerstenberger,3 and again by Hess.4 Orange juice was the chief constituent of a fruit mixture used by Gladstone5 in treating certain cases of marasmus. This mixture, of which he used a surprisingly large amount—24 ounces a day—consisted of 2 parts of orange

From time immemorial substitutes for human milk have been sought in the mammary secretions of other animals. The inadequacy of such substitutes has been made apparent by the distinctly higher incidence of disease and death among artificially fed babies. Early attempts were directed toward the correction of the grosser difficulties. By variously modifying and diluting the substituted milks—more particularly cow's milk—these have been rendered more acceptable to the digestion and quantitative needs of the infant. As a result, artificial feeding in the hands of the skilful worker has been fairly successful if measured in terms of disease and death. But so concerned have we been with the more obvious disturbances that little attention has been paid to the possible deficiencies of these diluted milks which may render them greatly inferior to human milk as far as their growth promoting factors are concerned, although experience has taught that the addition

The more frequent use of low fat milk formulas, especially in certain cases of infant feeding, makes necessary some simple method of modifying the milk in homes where the fat content of the milk is unknown or a variable factor. Even when formulas furnishing larger methods of fat are desired, an easy and reliable method of modification, applicable to home conditions, will be helpful.There are already in general use several methods suited to meet the conditions for which they were devised. For example, if a high fat milk formula is desired, Holt's1 method of siphoning off the upper part of the milk is in every way adequate; or, if one desires a 3 per cent. milk and has a 4, 4.5 or 5 per cent. milk, Schereschewsky's2 method may be employed, although according to Darling3 this has certain limitations, for the results are apt to be

The paucity of data concerning the magnesium needs of man at different periods of his development has stimulated further study of magnesium retentions in children. The first report1 from this laboratory, which included a review of the literature, was concerned primarily with a series of single ten day balance studies with individual children. Calcium and phosphorus retentions also were studied in order to determine if there are any interdependent relations among these three metabolites.The present report represents part of a nine month study of the growth, osseous development and mineral metabolism of 3 preschool boys aged 4 years 10½ months, 4 years 9 months and 3 years 3 months, respectively, at the beginning of the study and considers the magnesium retentions at three levels of ingestion, any one of which might occur in a seemingly well selected diet. Data pertaining to the calcium, phosphorus and nitrogen retentions and

The reports on the amount of the three metabolites—calcium, phosphorus and nitrogen—needed by children of a given age have varied, because, it is believed, there were differences in the growth pattern of the children studied, in the degree of saturation of the tissues at the time of the study and in the availability of the metabolites in the materials fed. Furthermore, the retention of calcium and nitrogen is influenced not only by the amount needed but by whether an adequate amount of phosphorus is supplied by the diet. In many of the studies only calcium balances were reported; comparisons, therefore, may not be valid. The problem is further confused by the fact that many of the studies have been of short duration. Continuous balance studies both with children and with adults have indicated that there is considerable variation from period to period; and although this is due in part to

In an attempt to determine the vitamin C needs of young children, three boys of preschool age were given during twelve successive periods constant weighed diets differing from period to period only in the amount of ascorbic acid contained therein. A 5-day preliminary period for physiological adjustment preceded each two consecutive 5-day metabolism periods. During four periods, a part of the vitamin was supplied by a synthetic commercial preparation.

In an attempt to determine the amount of magnesium needed by growing children, thirty-three balance studies have been made with children between 4 and 7 years of age receiving various levels of magnesium. Calcium and phosphorus balance studies were made simultaneously in order to determine to what extent these may have influenced the magnesium retentions. In the study, the influence of insufficient vitamin D and vitamin C was seemingly ruled out since the children received a constant and what was believed to be an adequate amount of vitamin D obtained from cod liver oil and viosterol, and vitamin C from canned tomato and orange juice given twice daily.

To meet the requirements for the other essential substances of the Vitamin B complex in Vitamin B1(thiamine) assays, early workers used autoclaved yeast. Because of the uncertainties involved in obtaining a yeast quite free from the vitamin in question, the use of autoclaved whey and autoclaved liver has been advocated since the thiamine in these apparently is more readily destroyed. For these assays it is customary to place the test animals on the basal ration at weaning, hold them until the body stores of B1are depleted, manifested by stationary weight, and subsequently for a given specified period add the material to be tested in amounts sufficient for considerably less than the optimum gain. Although theoretically it should be possible to use a test animal for successive assays, in practice it is customary to make only one assay with a given animal. Under these conditions, possible discrepancies in the basal ration may be masked, or the results may be modified by enrichments in the test material. Furthermore, when the basal ration is made up on the percentage basis, the amounts taken will vary with the appetite of the animal. Thus, in certain instances, less than the optimum amount of the other constituents of the Vitamin B complex may be taken. Therefore, to make sure that the basal ration is adequate, several successive assays should be made with the same animal, allowing sufficient time between tests for the animal to become depleted of its B1store. This would seem to be important, even though a negative control accompany the assays.To determine the value of certain basal rations for Vitamin B1assays, successive tests have been made with animals fed ad libituma basal ration consisting of B1-free casein 20 g, sucrose 62 g, Crisco 10 g, cod liver oil 2 g, and 4 g Hawk and Oser's salt mixture1with iron citrate and copper sulphate.

In animal studies pertaining to Vitamin E, varying amounts of fat have been used as essential constituents of the ration. Certain of these are known to have a specific influence on the rate of the oxidative changes in fats carrying the vitamins A and E. For example, wheat germ oil, a substance seemingly rich in Vitamin E., has been found to retard the oxidation of cod liver oil, as well as the destruction of Vitamins A and E; whereas lard hastens the destruction of these vitamins.1Correlating these findings with the results of animal experiments,2one is led to wonder if wheat germ oil is effective as an antisterility agent because of the presence of a specific vitamin, or because of its retarding influence on the oxidation of Vitamin A, a certain minimum of which is necessary for reproduction.It seemed possible that this might be determined by comparing the growth and reproductive behavior of animals receiving fat free rations, with animals receiving similar rations to which were added small amounts of wheat germ oil. We therefore have fed 3 groups of rats purified rations in which the Vitamins A and D were supplied by a cod liver oil concentrate (Oscodol∗). Vitamin B was furnished by starch free yeast.3In one group the ration was supplemented with 3% of wheat oil4; in another 12 gm. of lard was substituted for 27 gm. of cornstarch. All rations were made into a paste with distilled water, fresh mixtures being prepared approximately twice a week. TWO oscodol tablets, the equivalent of about 5% of the ration in cod liver oil, were added to every 488 calories of food. This, we have reason to believe, furnished a plethora of Vitamin A.5

The amount of vitamin B1destroyed in the process of dehydration and sterilization involved in the production of evaported milk has been variously reported. Hartwell,1by means of lactation tests, found approximately a 50% destruction in some of the milks tested, 33 cc. of fresh cow's milk being almost enough and 50 cc. quite sufficient to meet the needs of the lactating rat and 6 young, when used in conjunction with the basal ration; whereas 75 cc. of evaporated milk was found to be too little. Daniels and Brooks,2and Daniels, Giddings, and Jordan,3using a similar technique with a slightly modified diet, obtained similar results. Feeding tests with pigeons (Donath,4and Daniels and Brooks2) also indicated that the evaporated milks tested contained approximately 50% less vitamin B1than the raw milk used in comparative tests.Samuels and Koch,5on the other hand, by 2 different methods: a modification of the Hartwell1lactation test, and a direct feeding procedure, found only about one-sixth less vitamin B1in the evaporated milks, while Dutcher, Francis and Combs' believe the difference in the potency of raw and evaporated milk to be so slight as to be negligible. These authors state: “Vitamin B is not readily destroyed by the evaporation process used, and only under unusual conditions would we expect the deficiency of commercial evaporated milk to be due to the process of manufacture.”The lack of unanimity in these reports has led to a study of the vitamin B1content of raw Guernsey milk (4.5% fat) and commercial evaporated milk (diluted 1:1) by a modification of the 10-day bio-assay method of Schlutz and Knott.7Young rats at weaning were fed a purified vitamin B1-free ration consisting of: 20 gm. triple precipitated alcohol-extracted casein, 54.5 gm. cane sugar, 19 gm. Crisco, and 3.5 gm. Wesson's salt mixture.8In addition, each animal received 2 drops of cod liver oil.

During a recent study of the vitamin C needs of children which included determinations of the daily urinary excretions of ascorbic acid, one child developed a slight upper respiratory infection which interfered with night rest. He was given on 2 successive nights 2.5 grains of aspirin; and water ingestion was forced during 2 days. Since his food intake remained normal and his temperature was only slightly elevated, the experiment was not discontinued as is usual when a child who is under observation develops a cold. Analysis of the urine following aspirin administration showed an increased output of ascorbic acid. This was quite out of line with our general findings to the effect that following physiologic adjustment, at a given level of ingestion the daily excretions of ascorbic acid of the children under observation were surprisingly constant during the 10-day period of study (Everson and Daniels1). Was the increased excretion of ascorbic acid due to conditions producing the elevated temperature, the effect of the acetylsalicylic acid, or to a washing-out process following the larger water intake? That infections may deplete the stores of vitamin C has been suggested by Dry,2by Harde, Rothstein and Ratish,3and by Harde and Benjamin.4On the other hand, Giardina5has shown that sodium salicylate will precipitate scurvy and death in guinea pigs receiving diets containing an insufficient amount of the antiscorbutic vitamin in a shorter time than in pigs on similar diets with no sodium salicylate.To obtain further data regarding the effect of aspirin on vitamin C metabolism in the human organism, the 3 children between 4 and 6 years of age who were under observation were given constant weighed diets during which period the ascorbic acid intakes and excretions were determined daily.

During an investigation pertaining to the mineral deficiencies of milk, it was observed that the young, born of milk fed rats in February and March, 1926, were smaller, and their rate of growth was far less rapid, than that of any which we had heretofore noted in a long series of milk fed animals. These young were furthermore much smaller than young born of these same mothers during October and September, 1925. The appearance of the young in all groups (6) were so strikingly similar, even though the milk modifications were somewhat unlike, that it seemed as if the difficulty must be inherent in the milk, and not in the added inorganic substances. This was further emphasized by the fact that in two cases in which the mother rats were being used as controls, the animals were receiving only milk with the customary iron and iodine additions.To determine what constituent of this particular “winter” milk was lacking, we reduced the number of young in each litter to four, and added to the milk rations of the mothers the following substances respectively: Ca3(PO4)2, Vitamin B preparation, Yeast, and cod liver oil. In no case did we get satisfactory growth. Slight gains were observed with three of the cod liver oil groups. One group receiving the cod liver oil addition died, as did also the group receiving the Ca3(PO4)2.Besides the small and spindling appearance of these young, it was observed that the skin had a peculiar pink, yellow color, and the fur was very thin and peculiarly wiry. In spots it was quite gone, giving the animals a moth-eaten appearance. A somewhat similar condition in the fur of animals receiving a purified ration, containing cotton seed oil for its chief fat component, seemed to have been corrected by irradiating the food mixture with ultra violet light from a quartz mercury vapor lamp.

The Wide Range Achievement Spelling Test was administered to 64 aphasic subjects. Total errors on each of the 100 test words and errors made by subjects in each quartile were analyzed in relation to the logarithm of word frequency, and word length determined by number of letters. Both word length and word frequency were found to be significant variables in determining the spelling performance of aphasic subjects. Word frequency and word length were negatively correlated, and accounted almost completely for the errors on the test words in all segments of the population.

In an endeavor to determine the cause of the high infant mortality of milk-fed rats, reproduction, lactation and the manganese content of the young at birth, at weaningand there, after at various periods to sexual maturity have been compared in animals receiving Guernsey milk plus copper and ironwith those receiving the same ration fortified with manganeseas well as with stock fed animals. The lactating ability of the animals receiving the simple milk ration was specifically tested by exchanging their young for vigorous stock young. In a number of instances where the young of the milk-manganese low animals diedthey also were given stock young to raise. Records were kept of the amount of milk consumed by each animal during lactation.

Calcium, phosphorus, magnesium and nitrogen retentions in children of preschool age have been studied in relation to ascorbic acid ingestions and retentions during periods when the children were receiving diets which included 1 quart, 3 cups and 1 pint of milk, respectively. The influence of two levels of orange juice ingestion, 60 cc. and 120 cc., also has been considered. Variation in vitamin D as an influencing factor was seemingly ruled out since each child received approximately 3000 U. S. P. units per day. Each child, furthermore, was given a 10-minute exposure to ultra violet light from a mercury quartz lamp and lived in a room equipped with corex glass windows. The time spent out of doors showed no correlation with the retentions.

Fifteen iron and copper balance studies have been made with eight normal children ranging in age from 4 to 6 years. In a few cases successive studies were made with the same child.

The work recorded in the present paper, although begun with another purpose in mind, is the result of an attempt to find if there is any relation between attacks of gout and the amount of uric acid in the blood, or between such attacks and the amount of uric acid excreted in twenty-four hours. By means of the new method of Folin1 the surmises of earlier investigators that the uric acid content of the blood is increased in gout has been confirmed by Dr. Folin2 and coworkers in a certain number of cases. These findings, taken together with observations showing a retardation of uric acid in gout, are in accord with the hypothesis of Gerrod3 that the attacks of gout are due to increase of the uric acid content of the blood above its saturation point as a result of the inability of the kidney to excrete

In an endeavor to determine the amount of protein which children of preschool age should be given, nitrogen retentions at various levels of ingestion have been studied in children from 37 to 66 months of age. The data have been evaluated, first, in relation to weight, both actual and theoretical; and, second, in relation to the creatinine eliminations which were taken as a measure of muscle needs. The results based on the creatinine eliminations were found to be more consistent than those by other methods tested. Interpreting the data based on creatinine elimination in terms of theoretical weight of the children studied, it is concluded that children of the ages considered should receive approximately 3.2 gm. of protein per kilogram (N.×6.25) or 1.5 gm. of protein per pound in diets furnishing at least 50 per cent of the protein from animal sources.

Twelve manganese balance studies with seven children have been made at three different levels of ingestion. Within the limits of the study the amount retained was found to be proportional to the amount ingestedthus indicating that manganese is essential to the physiological development of children. It is suggested that the diet for children should contain between 0.20 and 0.30 mg. of manganese per kilogram.

An attempt has been made to determine if the high mortality of the suckling young of milk fed rats is due to a deficiency of the antineuritic vitamin content of the milk. Stock-fed rats, either just previous to or following parturition, were given various types of milk diets, some of which were distinctly lower in the antineuritic vitamin than others. The influence of the addition of substances known to be rich in the vitamin was tested, as well as the influence of certain inorganic substances.

Calcium, phosphorus and nitrogen balance studies with children of preschool age receiving diets composed of the same varieties of food but differing in amounts and therefore in the quantities of the inorganic substances contained therein have been considered from the standpoint of both height and weight. The vitamin D in all cases was controlled, and in so far as is known, adequate, thus ruling out any variation which might accrue from too little.

The investigation has included a study by means of the Hartwell method, of the antineuritic vitamin content of various forms of heat-treated milks used in infant feeding. The milks tested have included evaporated milk, two types of dried milk, a desiccated albumin-milk, boiled milk, and milk pasteurized both by the open and closed method (hold process.) With the exception of the milk dried by the roller process, all the superheated milks gave evidence of considerable destruction of the vitamin. The results with the open method, pasteurized milk tested, also suggested that there is some destruction of the vitamin; much less, however, than in either evaporated milk or milk dried by the spray process. Milk pasteurized by the closed method gave no evidence of the vitamin destruction. Milk heated to the boiling temperature quickly and cooled slowly seems to be somewhat affected. The results of tests with these were fairly comparable to those of the open method pasteurized milk. Milk boiled quickly and cooled quickly is little, if at all, affected. The results of the investigation suggest that temperature and aeration are important factors in determining the degree of destruction of the antineuritic vitamin in milk.

The renewed interest in the solution of the rickets problem is evidenced by numerous publications dealing with the subject from an experimental as well as from a clinical and social-hygienic standpoint. In the main, these communications have tended to verify the older ideas of the causation and treatment of rickets. The rôle of calcium, phosphates and cod liver oil has again been studied through animal feeding experiments, although little that is fundamentally new has been added to our knowledge. Instead of the old term, "bad hygienic surroundings," we now think more specifically of lack of sunlight.Not much light has been thrown on the question of the influence of heredity, using this term in a loose sense. While we are not even yet in possession of definite knowledge as to the exact parts played by calcium, phosphorus and possible antirachitic vitamins, we do know that their absence from the diet,

Recent observations to the effect that autoclaved whey is lacking in some essential component of the vitamin B complex other than thiamine1 cast some doubt on the results of a previous study which appeared to indicate that there is a 60 per cent destruction of thiamine in commercial evaporated milk,2 since in that investigation autoclaved whey was used with the basal ration to supply these other essential constituents. The increased use of evaporated milk, particularly for infant feeding, makes it necessary that the amount of destruction of thiamine be known. The feedings consisting of a mixture of evaporated milk and the usual amount of a vitamin-free carbohydrate, which have a high caloric value, may contain an insufficient amount of thiamine. This may account for the fact that many infants 5 or 6 months of age refuse to take sufficient food for normal gains in weight, even though the

There is some evidence that superheating destroys the antirachitic effect of irradiation.1In order to test this point further we have compared over a period of 10 weeks the growth performance of rats which were receiving a rachitic ration2with that of animals receiving (1) similar rations which had been irradiated; and (2) the irradiated ration which had been subsequently superheated. This rachitic ration which consisted of a mixture of grains was finely ground, mixed with distilled water and heated until it was of a thick gelatinous consistency. Since even at 15 pounds pressure mixtures of this consistency seldom reach throughout temperatures above 97° C., it was thought that results with these rachitic rations might not be valid. Therefore, we have tested the effects of the addition to the ration of (1) boiled milk; (2) irradiated boiled milk; and (3) irradiated milk which was subsequently autoclaved.In order to test further the effect of superheating on the antirachitic properties of milk, we have used in the rachitic ration comparable amounts of evaporated milk, as well as evaporated milk supplemented with calcium phosphate, thereby ruling out the influence of the possible calcium deficiency of the evaporated milk.The rickets ration was irradiated in thin layers (⅛ inch) for ½ hour at a distance of 2 feet. Part of this was then autoclaved at 15 pounds for 6 hours. The milk was irradiated in ¼ inch layers for 20 minutes at a distance of 2 feet. Before autoclaving this was diluted with distilled water and heated at 15 pounds pressure for one hour.The results of the investigation indicate that superheating, at least to the extent involved in the experiment, does not affect the antirachitic properties of food. This is shown not only by the animals which received the irradiated milks, but by those receiving the evaporated milk as well.

Rats fed on diets adequate in all other respects but low in the Vitamin A factor, develop, in the course of time, infection of the upper respiratory tract. The first symptoms of the dietary deficiency are snuffles, loss of appetite, and failure to gain. These animals invariably die unless appropriate dietary treatment is introduced fairly early in the course of the infection. Macroscopic examination of the various organs of these animals, with the exception of the aural and nasal passages, which have been found filled with pus, shows nothing consistently abnormal. Occasionally the lungs are infected, often the intestines are filled with gas and greatly distended. Death in these animals seems to be the result of an infection superimposed on tissues which have been altered by the dietary deficiency.The excessive reaction to infection of the upper respiratory tract (nasal and aural passages) of the artificially fed baby and the low incidents of such infection amongst breast fed babies, suggests that in the former case as in the rats, we are dealing with an infection superimposed on tissues which have been altered by a dietary deficiency.The excessive reaction to infection of the upper respiratory tract (nasal and aural passages) of the artificially fed baby and the low incidents of such infection amongst breast fed babies, suggests that in the former case as in the rats, we are dealing with an infection superimposed on tissues which have been altered by a dietary deficiency.The possibility of the occlusion of Vitamin A in the calcium soap excreted by the artificially fed baby, and the consequent failure to absorb enough to meet the physiological needs, was suggested by Daniels and Armstrong in 1923.1Acting upon this suggestion a comparative study of the Vitamin A excretion by way of the gut, in an artificially fed and in a breast fed infant, has been made.

Hartwell's1method of determining the Vitamin B content of foods differs from that of other workers, in that it consists in measuring the effects of a given ration on the suckling young. Either just before or just following parturition the mother animal is put on a high protein ration containing all the known necessary constituents, with the exception of Vitamin B. In the absence of an adequate amount of Vitamin B the suckling young gain normally for about 13 days, when they suddenly develop convulsions, manifested by general muscular incoordination. This condition is frequently accompanied by unusual outcries, and dragging of the hind legs. The baby animal gasps for breath, and finally dies within a few hours. That these animals do not die of insufficient food is indicated by the fact that milk is very frequently found in the stomachs. When adequate amounts of Vitamin B are added to the ration the young animals develop normally and are weaned at the usual time.By this method,2comparative studies of fresh and evaporated milks have indicated that evaporated milk is quite deficient in Vitamin B. Since these findings are not in accord with results reported by Gibson3on pigeons, dogs, and pigs, nor with the recent work of Dutcher,4arrived at by the more usual method of feeding the growing young directly, it seemed possible that the untoward symptoms in Hartwell's animals might be caused by a calcium deficiency, or a lack of Vitamin D. Previous experiments showed that in the process of evaporation the calcium and phosphorus in milk is made less available.5We have, therefore, repeated Hartwell's experiments, making certain additions and modifications in the ration. In our experiments the pregnant animals, which had received our stock ration throughout the gestation period, were given the experimental ration just previous to parturition.

By suitable methods the radio-active substance of cod liver oil can be separated from the oil, and prepared in concentrated form for therapeutic purposes. Recent work by Hart, Steenbock and Hoppert1has suggested that such concentrates under certain conditions may fail to be effective. In a study of calcium and phosphorus balances it was observed that the addition of cod liver oil to the ration of milking goats increased the calcium retention.2The cod liver oil concentrate (non-saponified fraction), however, was without effect unless it was previously dissolved in oil. The results with the concentrate administered dissolved in oil were comparable to those with the non-saponified cod liver oil.Since goats are habitually herbivora, taking little or no fat, as such, in their food, it seemed probable that quite different results might be obtained with the omnivora. Drawing conclusions from the work of Hart and Steenbock with goats, one is led to question the availability to the human organism of a concentrate unless given in oil, or in close proximity to a meal which carries fat.In the study herein reported we have fed young rats a rachitic4ration which supplied fat only as it was present in the various cereals of the mixture. To this was added a cod liver oil concentrate equivalent to 1 per cent of cod liver oil. With one group the concentrate was pulverized and dissolved in corn oil (2 per cent of the ration). A second group received the same amount of the concentrate, which was mixed with water and incorporated in the ration. Control animals were given the ration to which was added 1 per cent cod liver oil mixed with corn oil. The rate of growth of the animals on these various food mixtures is summarized in the following table: