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SUMMARY 1. The substances chromium-51 (51CrCl3) and phenolsulphonphthalein (phenol red; PR) were compared as non-absorbable indicators in the human stomach after alteration of ionic permeability by taurocholic acid. 2. Control and test solutions containing 10 mm taurocholic acid and indicators at pH 1 were instilled into the stomach and sampled immediately and after 15 min. The ratios of the initial and final concentrations of the indicators (Ci/Cf) were compared. 3. Correlation coefficients of the Ci/Cf ratios for the two indicators were 0·91 in control studies and 0·75 after taurocholic acid instillation; there was no significant difference between either indicator. During taurocholic acid instillation, Ci/Cf values tended to fall compared to controls. 4. In a smaller number of subjects in whom polyethylene glycol (PEG) was also measured as a non-absorbable indicator, results were similar to those obtained with 51Cr and PR. 5. 51Cr, PR and PEG are comparable indicators in the normal human stomach and when it is made abnormal by a lipid-soluble agent such as unionized taurocholic acid, though the correlation between indicators is reduced in the abnormal stomach. 6. No evidence of increased absorption of any indicator was found in spite of the increased ionic permeability produced by taurocholic acid.

— Variations in the form and number of root canals are greater in the mesial roots and in some specimens the mesial root was divided into two. The main variations show multiple canals with subdivisions and communications frequently with one common apical foramen. Little difference was noted between root canals in young teeth and those in heavily worn mature teeth.

The root canal systems of the deciduous teeth have been demonstrated by the epoxy resin injection technique. A major difference is noted between the simplicity of that seen in the incisors and the molars.

Both Belostoma and Ranatra possess I–II, subepimeral, thoracic subalar, and abdominal subalar air stores. In Belostoma, unlike Ranatra, the subepimeral air store is greatly enlarged, the abdominal subalar store is partially exposed to the water, and a fully exposed ventral abdominal air store is also present. All the air stores of Ranatra are normally concealed. The mesothoracic and metathoracic spiracles, which open onto the I–II and subepimeral air stores respectively, are of limited permeability. They appear to have less respiratory importance than the large and highly permeable first abdominal spiracles, which lie in the subalar air space and can probably exhale and inhale large amounts of air. The large eighth abdominal spiracles, which lie at the base of the siphon or retractile organ, can also inhale or exhale much air in Ranatra but appear to be mainly exhalant in Belostoma. The smaller second through seventh abdominal spiracles structurally resemble the eighth ones in Belostoma and open onto the ventral abdominal air store. In Ranatra they appear to have no significant respiratory function. Both genera obtain atmospheric air and give off exhaled air by means of the posterior retractile organ or siphon. The two types of air appear to follow different pathways in the two genera. In Ranatra atmospheric air appears to enter the tracheal system mainly or entirely through the eighth abdominal spiracles and then passes through the first abdominal spiracles into the subalar space. Exhaled air follows the reverse pathway. In Belostoma, however, atmospheric air probably enters the tracheae mainly through the first abdominal spiracles; it is conveyed to these spiracles from the retractile organ through the subalar space or, more indirectly, through the ventral abdominal air store. Air exhaled through the first abdominal spiracles follows the reverse route; the eighth abdominal spiracles can also exhale directly into the base of the retractile organ. During underwater respiration the abdominal portion of the subalar air store appears to be the main reservoir for oxygen. The subalar oxygen is initially atmospheric, and is supplemented, during submersion, by other sources of oxygen. Belostoma may use its exposed ventral abdominal air store, and its partially exposed abdominal subalar one, as “physical gills”; both these stores communicate with the inhalant first abdominal spiracles. Ranatra, none of whose air stores are normally exposed, appears, to be less capable of utilizing dissolved oxygen, but the considerable amount of atmospheric oxygen in the elongated siphon may be inhaled, during submersion, through the eighth abdominal spiracles. In both genera the thoracic air stores appear to be of less respiratory importance than the abdominal ones. They do not appear capable of obtaining large amounts of oxygen, and the thoracic spiracles are relatively impermeable. All the air stores, however, serve to protect the spiracles against the entry of water, and also contribute to the body's hydrostatic balance. It is also possible that some of the air stores play a role in pressure reception. The literature indicates much intergeneric variation in the respiration of Belostomatidae and Nepidae. In the Belostomatidae there is considerable variation in the extent of the ventral abdominal air store and in the roles of the subalar air store and the spiracles. The Nepidae show differences in their ability to utilize dissolved oxygen and in the extent of the subepimeral air store.

The loral lobes of the hemipteran cranium are described and their possible homologies are discussed. It is proposed that the hemipteran head arose from a hypothetical first stage which had many generalized pterygote characteristics, including the lack of a prepharynx. From this initial stage, a head with a prepharynx, a functional [as apposed to morphological) mouth, and loral lobes could have developed in at least three ways, each of which assumes a different interpretation of the loral lobes.Of the three theories discussed here, the hypopharyngeal one is, in my opinion, the most satisfactory, and the clypeal one the least. Although the clypeal theory is the only one of the three which is strongly supported by embryological evidence, it can also be more strongly criticized than the other two. Major drawbacks are (1) its complexity, (2) its interpretation of the functional mouth, and (3) the fact that it is inconsistent with the innervation of the loral lobes and with their condition in the Hydrocorisae.Supporters of the genal–subgenal theory cite the sternal origin of the hypopharynx as a major objection to the hypopharyngeal theory. This rather questionable criticism is, in my estimation, more than compensated for by the drawbacks of the genal–subgenal theory which include (1) its relative complexity, (2) the lack of any definite embryological evidence for it. and, perhaps most serious, (3) its interpretation of the loromaxillary cleft as an intersegmental boundary.The hypopharyngeal theory has none of the drawbacks of the other two except the lack of conclusive embryological evidence. It is the simplest of the three theories, explains both the typical morphology of the loral lobes and their modification in the Hydrocorisae. and is consistent with the generally accepted views of the phylogeny of the Heteroptera.

1. The clinical and hematological features of seven cases of nonspherocytic congenital hemolytic anemia occurring in four different families are presented, together with family studies. Four cases resemble Selwyn and Dacie’s Type I and three cases their Type II. Cases in the literature similar to our cases are reviewed. 2. The Type I cases showed the following features: normocytic or slightly macrocytic anemia with mild hypochromia and some stippling; a decreased or normal osmotic fragility of fresh blood and a decreased fragility of incubated blood; a slightly increased autohemolysis corrected by glucose and by ATP. The family history was positive and clinical onset was usually in adult life. Survival studies suggest that splenectomy may result in partial remission. 3. The Type II cases showed the following features: a marked uniform macrocytosis with numerous Pappenheimer bodies (postsplenectomy); a normal osmotic fragility of fresh blood and an increased fragility of incubated blood; an increased autohemolysis uncorrected by glucose but corrected by ATP. The family history was often negative and clinical onset was usually in infancy. Splenectomy in general appeared to produce no benefit. 4. The classification and pathogenesis of these anemias is discussed. It is pointed out that Type I is not a homogeneous group, and that our cases simply represent one subgroup of this type. Type II appears to be a more homogeneous group. Preliminary biochemical studies suggest the difference in clinical types may be determined by differences in biochemical defects.

Colour photomicrography of particles in Brownian movement has been achieved on High-Speed Ektachrome film using a flash source giving about 200 joules in 250 µsec. The design and operation of a prototype apparatus is described, and its potentiality for further development discussed.

By employing a version of industrial slush casting to conventional silicone rubber moulds and simultaneously applying internal pressure, accurate epoxy resin casts may be obtained, varying by less than 1.0% from the original. This is made possible by the construction of a machine which rotates the moulds through all axes. When applied to fossil crania these moulding and casting methods not only accurately reproduce the external morphology, but when access permits, simultaneously copy the endocranium. The dimensional accuracy is reproduced throughout for any given measurement. By using a variety of colouring methods these casts also produce replicas which closely approximate the appearance of the original.

A possible explanation of how the ancestral hemipteran head could have evolved from a basic pterygote plan is presented. It is proposed that the lateral cranial region descended ventrally as a parietal lobe, giving rise to the lamina maxillaris and maxillary plate, while the hypopharynx expanded laterally to form the loral plate. The maxillary and mandibular appendage anlagen produced only the stylets, and did not contribute to the head capsule. These stylets were first concealed in the atrial cavity between the parietal lobe and the hypopharynx; the cavity later closed laterally to form separate stylet sacs. The food and salivary pumps arose through the lateral closure of the cibarium and salivarium respectively. These changes brought about a closure of the external clefts between various parts of the cranium. In some modern Hemiptera the lines of fusion have been retained as sulci; in others they have disappeared. Although the homopteran cranium is very similar to the hypothetical ancestral head, the heteropteran cranium shows further modifications, such as the formation of a posterior cranial wall, the loss of the tentorium, and the obliteration of many external sulci. Both modern hemipteran orders show much variation in cranial structure.

The labial skeleton and musculature in representatives of six families of Hydrocorisae are described. The Notonectidae, Naucoridae, Gelastocoridae, Belostomatidae, and Nepidae all possess four-segmented labia with a relatively similar musculature. In Heteroptera the labium is adapted to a fluid diet and thus differs from that of generalized mandibulare insects. The labium of typical Hydrocorisae is compared with that of generalized insects, and the theories of previous authors regarding the possible homologies in the two groups are discussed.In the Corixidae the labial skeleton and musculature are highly modified, differing considerably from those of the other five families of Hydrocorisae. The structure is shortened and broadened, lacking a clear four-part segmentation. Several possible interpretations of its homologies with the labium of typical Hydrocorisae are discussed. Finally, the possible phylogenetic implications of the labial morphology in these six families are considered.

This paper deals with the small problems which arise in the plaster shop, and are a source of annoyance and cost if handled incorrectly. The grade of plasters used, manner of handling, method of payment, extent of reinforcement of molds, care of benches, correct procedure in making the various parts and types of molds, are all touched on.

says that every manifestation of the industrial society in cities and buildings during this period required the prefix 'ugly'.l Time and ivy have softened the rough, pseudoItalian surfaces of Cornell's first buildings-White, Morrill and McGraw halls. These sturdy monuments have aged well but they never deserved the adjective ugly. More importantly, their siting, massing and rugged stonework command our respect for the talent of the era. The craggy line of buildings is appropriate for the dramatic site, and they are powerfully but respectfully disposed in relation to one another and their neighbors. This picturesque composition is a result of a curiously effective interaction between the concerns and tastes of two very different clients and interposition, at a crucial moment, of the landscape design ideas of Frederick Law Olmsted. We can see how this came about by reviewing the architectural interests and experience of the two principal clients-Ezra Cornell, the founder, and Andrew Dickson White, the first president-and by examining the critical decision on a site, the development of plans for a quadrangle, the strange 'competition' for the design of the first building, and finally Olmsted's contribution of an ordered composition. Ezra Cornell was a practical builder. His role in the development of the Cornell campus was controlled by his concern for firmness, commodity and economy in building. He did care about Vitruvius' third principle of good architecture-delight-but he was such a pragmatic man that he placed economy in building and savings in architectural fees before what he considered architectural extravagance. He preferred a plain style.

The real part of the virtual Compton amplitude can be directly determined from measurements of electron (or muon) bremsstrahlung or pair photoproduction. In general, the interference of the Compton amplitude with the Bethe-Heitler amplitude for pair production or bremsstrahlung yields a contribution to the cross section which is antisymmetric when the leptons are interchanged. This interference contribution thus produces different cross sections for electron and positron bremsstrahlung at a given scattering energy and angle. Also, the counting rate for pair production will depend on which lepton has the greater momentum. The determination of the real part of the Compton amplitude would supply information on the isobar resonance shape, test the dispersion relation for the forward amplitude, and resolve uncertainties in the determination of the nucleon resonances. A simple estimate for the lepton asymmetry of the pair production cross sections due to the forward Compton amplitude is given in addition to a complete calculation of the effect of the first nucleon resonance using the isobar model. The results are also discussed for nuclear targets. For the latter case, a broadening of the isobar decay width due to absorption in the nuclear medium must be taken into account. (Author)

under several other experimental conditions, including hypothermia (2-5 C), hyperthermia (34-36 C), and the supine position which produced a trancelike state in Crocodilians (Parsons and Huggins, 1965a, 1965b). In order to complete these preliminary studies, a new group of animals was given multiple implantations over the cerebral hemispheres and a pair of electrodes on the right and left olfactory bulbs. The recordings from the olfactory lobes presented a very interesting and clear-cut electroencephalographic pattern and also showed such definite responses to stimuli as to be worthy of further study and separate discussion, especially in view of the current interest in olfaction and the

Hour-degree soil temperature summations above 42°F at Rhagoletis pomonella (Walsh) pupal depth were obtained from late April to completion of adult emergence in August1964-65, 1967-68. A good correlation between 1st adult emergence and temperature summations was shown by totals of 24,620 hour-degrees in 1964 and 23,706 hour-degrees in 1965. On the day of mean peak emergence (August 1) in 1964 the summation was 32,256 hour-degrees. In 1965, on the day of mean peak emergence (July 24), the temperature summation was 32,202 hour-degrees. with a second setting of the thermograph bulb in 1967, temperature summations at 1st adult emergence were 18,567 hour-degrees in 1967 and 20,699 hour-degrees in 1968. Temperature summations at day of mean peak emergence were 25,548 and 26,641 hour-degrees in 1967 and 1968, respectively. Daily temperature summations exceeded 500 in late July. These data indicate that the times of 1st emergence and mean peak of emergence of apple maggot may be closely determined for any1 site by summing soil temperatures at pupae depth following a preliminary season’s record of soil temperature summations and emergence data. There was no correlation between dates of bloom of McIntosh and temperature summations. Periods of adult emergence from carryover pupae from 8 ‘Lobo’, ‘Cortland’, and ‘McIntosh’ trees for two 5-year periods show that since 1963 there were 14 carryovers to the 2nd season, 11 carryovers to the 3rtl season, 6 carryovers to the 4th season, and 3 carryovers to the 5th season.

The spiracular chambers of the three anterior pairs of spiracles are described, and their relationships with the air stores on the body are discussed. Morphological variations in the spiracular chambers of Ambrysus, Notonecta, and Hesperocorixa appear to be correlated with the manner in which these insects obtain atmospheric and dissolved oxygen.

The cibarial food pump of heteropteran insects conveys fluid food from the piercing stylets to the pharynx. In aquatic Heteroptera the pump also grinds and filters particulate matter in the food stream. The pump's sclerotized triturating devices differ from one family to the next and are often quite elaborate: because of their small size they are best studied by means of the scanning electron microscope. In Notonecta the main triturating devices occur on the transverse plates of the epipharyngeal roof of the pump. They consist of a complex anterior zone with raised nodes and bifurcating longitudinal ridges, and a simpler posterior zone with small nodules. Additional triturating surfaces occur on the hypopharyngeal floor of the pump. The oblique folds of the epipharynx, which lie anterior to the transverse plates, play only an accessory role. The fine structure of the grinding surfaces on the transverse plates of Gelastocoris (Gelastocoridae), Ambrysus (Naucoridae), and Aphelocheirus (Aphelocheiridae) is here briefly described and compared with that of Notonecta.

A method for gridding scanning radiometer (SR) data is outlined in complete detail. This gridding method, coupled with a suggested display technique, enables one to produce a real-time quantitative display of APT service SR data with only minimal computer capability.

1. Labelled testosterone, injected directly into the ventral prostate of castrated rats became associated, in part, with a cytoplasmic high-molecular-weight fraction, fraction ‘A’. 2. The label present in fraction ‘A’ was found to be mainly associated with dihydrotestosterone. 3. Unlike fraction ‘A’ from testosterone-pelleted castrated rats, fraction ‘A’ obtained from untreated castrated rats, 48h or more after castration, was strongly inhibitory towards Escherichia coli RNA polymerase in vitro. 4. The inhibition of RNA polymerase by fraction ‘A’ from castrated rats was not changed by the addition of testosterone or dihydrotestosterone in vitro, but pre-heating it to 80°C resulted in a loss of its inhibitory capacity. 5. Fraction ‘A’ from castrated rats contained ribonuclease activity. The elution profile of ribonuclease activity from Sephadex columns indicated that this activity was responsible for the inhibitory effect on the RNA polymerase assays. 6. It is concluded that, unlike the inhibitor present in the uterus of ovariectomized rats (Talwar, Segal, Evans & Davidson, 1964), no direct connexion exists between the steroid-binding capacity of prostatic fraction ‘A’ and its effect on E. coli RNA polymerase activity in vitro.

When totally submerged beneath the surface of the water, Belostoma and Ranatra respire by means of air stores which adhere to their bodies and which communicate with the spiracles. The mesothoracic spiracle lies between the prothorax and mesothorax; the metathoracic and first abdominal spiracles lie posteriorly in the mesothorax and metathorax, respectively. All three spiracles possess a cuticular sieve-plate with a network of trabeculae. The mesothoracic and metathoracic sieve-plates have an inner membrane which appears to limit their permeability, especially in Ranatra. The first abdominal sieve-plate, in contrast, lacks the inner membrane and is penetrated by large lacunae in both genera; this spiracle is probably capable of exhaling and inhaling large amounts of air. The mesothoracic and metathoracic spiracles appear to be of less respiratory importance. The amount of air which can pass through their sieve-plates and (or) open ecdysial scars is limited in Belostoma and may well be negligible in Ranatra.

I N RECENT years many urban universities have decided that life in the city is one of the assets of civilization. Some of them are developing new attitudes toward the potentials of their city sites, toward their neighborhood environments, and toward local urban-renewal policies. It would be incorrect to claim that a permanent peace has ended warfare between universities and cities; the current state of affairs is more like a truce. The war has never been very fierce, and neither party has gained many worth-while objectives. The strategy of the universities has been characterized either by retreat before the advance of the city or by voluntary isolation from it. The tactics of the universities and their scholars have been limited to occasional sallies from their ivory towers to throw fine intellectual dust, verbal pebbles, and occasionally a useful critical rock at the follies of cities. For their part, city officials and most citizens hardly knew that the universities were there. They did little or nothing to preserve and advance educational institutions when they were threatened by physical and social change in the city. Now, during the suspension of hostilities brought about by a recognition of common interests, some urban universities and city governments have begun to negotiate the terms of a limited truce and joint action in city-university renewal. In I959, rapprochement between universities and cities was assisted by the passage of Section I I2, an amendment to the National Housing Act. This legislation encourages a limited partnership between the city and the university in urban-renewal projects of direct concern to both. A city may receive credit for recent acquisition of university land and relocation expenditures near an urban-renewal project as part of its share of the cost of federally aided renewal projects. The Association of American Universities was very active in securing passage of this legislation. Urban universities needed more effective urban-renewal programs in their own back yards. In the ten years before the adoption of Section II2, many urban universities had benefited directly or indirectly from urban-renewal programs. Land cleared in urban-renewal projects was sold for campus

The food pumps of ninny Hydrocorisae contain devices for straining or masticating ingested foods. In the Belostomatidae and Nepidae these consist of minute, sclerotized processes on the anteclypeal epipharynx. The cibarial dilator muscles are not subdivided, and the anteclypeus is unmodified. The Gelastocoridae, Ochteridae, Notonectidae, and Naucoridae have more complex epipharyngeal and hypopharyugeal devices (ridges, folds, hairs, or "teeth") in their tripartite, cibarial pumps. Their cibarial muscles are subdivided into four groups, and their anteclypei are anteriorly broadened and fused with the loral plates. The grinding and filtering devices of the Corixidae are very elaborate. Their food pumps are bipartite and controlled by both pharyngeal and cibarial muscles, the latter being divided into two groups. The corixid anteclypeus is broadened but not fused with the loral plates.These masticating or straining devices appear to be specialized rather than primitive features. It is proposed that they arose independently at least twice and possibly three times in the Hydrocorisae. It is also suggested that the ancestral Hydrocorisae gave rise first to the Belostomatidae and Nepidae, then to the Corixidae, still later to the Gelastocoridae and Ochteridae, and finally to the Notonectidae and Naucoridae.

The incubation of intact blastoderms from 48 hr chick embryos with 4- 14 C-testosterone resulted in the production of at least 5 metabolites, 3 of which have been positively identified as 5β-androstane derivatives. Extensive conjugation of the major metabolite (5β-androstane-3α,17β-diol) also took place. These findings may be relevant to the early stages of erythropoiesis in the chick embryo.

The salivary pumping apparatus in representatives of the aquatic family Belostomatidae (Insecta) is discussed. Observations were based upon dissections of adult Lethocerus and histological serial sections through the heads of nymphal Belostoma. The simple, two-layered salivary pump, its afferent and efferent openings, and the paired afferent and single efferent ducts are described. Also discussed are the mechanism of the pumping apparatus and its relationship to other endoskeletal structures. The pump and efferent duct are hypopharyngeal specializations in the Heteroptera, the efferent duct originating as a groove in the floor of the hypopharyngeal lobe. In Belostomatidae this groove is closed anteriorly, but caudally it remains open ventrally.