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Five new species of Tylenchus Bastian, 1865 from the Canadian high Arctic are described. T. neodavainei n. sp., differs from T. davainei in having finer annules on the lip region and a more slender body. T. stylolineatus n. sp. differs from T. (Tylenchus) arcuatus in having a lower lip region, finer lip annulation, and spear knobs rounded. T. hazenensis n. sp. differs from T. (Filenchus) thornei in not having an offset lip region which is finely annulated and a needle-shaped tail terminus. T. hazenensis differs from T. (Filenchus) ruatus in the ratio between the anterior and posterior portions of the spear length, the tail proportionally shorter and broader, and the basal esophageal bulb not exceptionally elongated. T. aquilonius n. sp. differs from T. (Filenchus) orbus in having a more slender spear, an ovate median bulb, excretory pore well posterior to the nerve ring, and coarser body annulation. T. cylindricaudus n. sp. differs from T. aquilonius n. sp. in having a slender body, the tail more cylindrical, and body annulation indistinct.

The adult and some of the larval stages of Notocotylus stagnicolae Herber, 1942 (family Notocotylidae) are redescribed and some details of their biology given.

An experimental study of Trichinella spiralis was made in white mice and white rats to determine the times of the final molt, free spermatozoa formation, ovulation, and insemination.The following results were obtained. In mice, the final molt began in about 27 hours and was completed at 33 hours after infection. Free spermatozoa were formed, in mice, at the 26th hour after infection. Ovulation was found to occur at the 37th hour after infection in mice and at the 30th hour in rats. Insemination occurred at the 37th hour after infection in mice and at the 32nd hour in rats. Ovulation and insemination were independent processes. The copulatory tube may be a modified structure of the cuticular lining of the cloaca.

A cause of swimmer's itch in the lower Ottawa River is Trichobilharzia cameroni sp. nov. Its life cycle has been completed experimentally in laboratory-bred snails and in canaries and ducks, and the various stages are described. The eggs are spindle-shaped. The sporocysts are colorless and tubular. Mother sporocysts become mature in about a week. The younger daughter sporocyst is provided with spines on the anterior end and becomes mature in about three weeks. The development in the snail requires from 28 to 35 days. A few cercariae were found to live for up to 14 days at 50 °C., although their life at 16° to 18 °C. was about four days. Cercariae kept at room temperature for 60 to 72 hr. were found infective. The adults become mature in canaries and pass eggs in about 12 to 14 days. Physa gyrina is the species of snail naturally infected. It was found in one case giving off cercariae for five months after being kept in the laboratory. Domestic ducks were found to become infected until they were at least four months old, with the parasites developing to maturity in due course; no experiments were made with older ducks. Furthermore, miracidia were still recovered from the faeces four months after the duck had been experimentally infected, and it is suggested that migratory birds are the source of the local infection.

Three new species of the genus Hemicydiophora, closely related to H. similis Thorne, 1955 and H. silvestris Jenkins and Reed, 1964, are described. These are H. vivida, H. shepherdi, and H. minora. H. vivida differs from H. silvestris in the more anterior location of the vulva, the smaller relative length of spear to total body length, the hemizonid covering three annules, and the pattern of the en face view being different. H. shepherdi differs from H. similis in having a smaller number of annules between vulva and anus, and a smaller and elevated labial disc. H. minora differs from the above-mentioned species in being the smallest nematode and in having the excretory pore more anterior in location and a greater relative length of spear to total body length.

Five new species of Criconemoides Taylor, 1936 are described. Criconemoides bakeri n. sp. resembles C. annulatum Cobb, in Taylor, 1936, but differs in having a much smaller number of annules and the head region not set off by a constriction. Criconemoides petasus n. sp. resembles C. annulifer (de Man, 1921) Taylor, 1936, but differs in not having a basal cephalic annule, in the spear being shorter, and in the body annules being well separated by incurvations. Criconemoides hemisphaericaudatus n. sp., with males present, appears to resemble C. simile (Cobb, 1918) Chitwood, 1949. It differs in having a greater number of annules, the excretory pore more posterior in position, and the anterior vulvar lip simple. Criconemoides rotundicaudatus n. sp., with males present, also resembles C. annulatum. It differs in having the first two annules not set off by a constriction, and in having the first few annules usually packed together. The anterior vulvar lip is simple and inconspicuous. It differs from C. simile in having a longer spear, a larger number of annules, the excretory pore more posterior in position, and the anterior vulvar lip simple. Crionemoides quasidemani n. sp. is close to C. demani Taylor, 1936. It differs in having the excretory note more posterior in position, the second cephalic annule not thicker than the first annule, and the caudal half of the tail attenuated. It differs from C. princeps Andrássy, 1962 in having a greater number of annules, shorter spear, and more slender tail, and in the absence of cuticular patches on the lateral aspect.

Nematodes having the general characters of Ditylenchus destructor Thorne, 1945, from the potato, bulbous iris, and dahlia, did not reveal any significant difference in the basic structures to suggest the presence of more than one species. However, due to host influence, there may be some variation in total length, width, number and arrangement of sex cells, length of oesophagus, length of spear, and tail shape. Nematodes from potato were successfully transferred to dahlia and carrot, and from iris and dahlia to potato.Specimens of D. destructor from potato interbreed freely with specimens from bulbous iris and from dahlia. Evidently these nematodes from the three hosts are the same species, i.e., D. destructor.Among the ratios used, the values of c in the case of males and that of "V%" have some support from the data.

Criconema bakeri n. sp. was collected in Algonquin Park, Ontario, Canada, from soil under a sugar maple tree (Acer saccharum Marsh) in July, 1961. It is similar to Criconema. inaequale Taylor, 1936, in having transparent cuticular outgrowths that are not in definite longitudinal rows, but differs in that the anterior flap of the vulva extends backward characteristically, overlapping most of the following annule, which is pressed caudad showing a button-like projection, distinguishing it from C. inaequale and other species.

Criconema celetum, n, sp., is described from African violets collected at St. Laurent, Quebec. The body has 40–43 annules, each having a row of spines except at the caudal end; those near the middle of the body each having a row of about 70 spines. The head consists of two annules with spines, the first 22–28 μ in diameter and the second 19–23.5 μ. The annules at the caudal end have spatulate projections each with several spines. The spear is 84.3–95 μ (with one exception, 100 μ) long. The body is coated with soil particles under and around the spines.

Structural differences in the spermatheca and sperm cells of Ditylenchus and Tylenchus were found to be of significant value in the separation of these two genera. In Ditylenchus, the spermatheca is a long tubular structure located between the uterus and the oviduct. The sperm cell consists of two parts: a dense nucleus and a large translucent vesicle. In Tylenchus, the spermatheca, when present, is in the form of a diverticulum of various shapes, arising at the junction of the uterus and the oviduct. The translucent vesicle is absent within the sperm cell.

Three new species of the genus Tylenchorhynchus Cobb, 1913 from Canada are named and described. Tylenchorhynchus irregularis n. sp. differs from all closely related species in the irregular width of the cuticular annulation, especially in the posterior half of the body. T. longus n. sp. is similar to T. superbus Allen, 1955 but differs from this species in relative tail length and annulation of the tail terminus. T. laminatus n. sp. resembles T. leptus Allen, 1955 but differs in the details of the lip region, spear length, and laminated annules.

Summary Seventy-two children with nutritionaliron-deficiency anemia were given iron-dextran complex intramuscularly. The average gain in hemoglobin in the first and second weeks after intramuscular therapy was 2.1 and 2.2 Gm. per cent in the 28 uncomplicated cases, 1.8 and 1.7 Gm. per cent in 19 cases complicated by infection, and 0.7 and 1.3 Gm. per cent in 9 cases complicated by lead poisoning. In 12 patients, with uncomplicated iron-deficiency anemia, receiving weekly injections, the gain for the first week was 1.4 Gm. per cent and 2.3 Gm. per cent for the second week. In the oral-iron group, this gain was about 1.0 Gm. per cent each week. Only one patient had staining of the skin at the site of injection. One patient developed urticaria after an iron-dextran injection. From these observations, it wouldappear that in situations where a rapid elevation of hemoglobin is important, injection of iron intramuscularly is desirable. Intramuscular iron also provides for a faster and surer way of replenishing depleted iron stores. Another indication for intramuscular iron is that of a careless mother who might not give the oral medication.

Specimens of a pure line population of Ditylenchus destructor were studied. The female reproductive system is well differentiated into the ovary, oviduct, and uterus. The last is further differentiated into the seminal receptacle, quadricolumella, and uterus proper. There is a postuterine pouch, and this, with the vulva, is also described. The functional regions of the male reproductive system are distinct: the testis, vas deferens, seminal vesicle, and ejaculatory duct.The posterior ends of the two subventral esophageal glands extend caudad to about the same level, each with a small nucleus. The large dorsal gland, with a conspicuous, larger nucleus, extends behind the esophago-intestinal junction. The esophageal tube leaves the esophagus on the inner surface of the dorsal gland, just behind the subventral glands, where it joins the intestine. A pair of very small cells guard the entrance of the esophagus into the intestine.

Several males and females of an undescribed nematode genus of the subfamily Tylenchinae were found in soil around grass collected from a location not far from Peyto Lake in the Rocky Mountains of Alberta. A new genus and new species, Dactylotylenchus crassacuticulus, is herein described to accommodate this new taxon, which is significantly different from other genera in the subfamily, in possessing a finger-like labial framework and a thick cuticle.

A study has been made on the development of the stichosome in Trichinella spiralis. Stichocytes are seen as cuboidal cells in larvae six days after infection. During the course of development, the stichocytes gradually arrange themselves in two rows above the oesophagus and elongate transversely, tending to dovetail alternately opposite each other. The number of these cells in larvae taken 13 days after infection is only half that observed in the mature larvae. Each stichocyte takes a spiral course as the elongation continues. Superficially this results in an apparent duplication of the number of rectangular cells seen. In fact, the stichosome comprises a row of about 24 to 30 unicellular, binucleate gland cells. Each has two coils and somewhat resembles a spring in form. The intestinal gland cells also originate as two cuboidal cells. These undergo separate development into two gland cells looping around the oesophageal–intestinal junction.

Paratylenchus robustus n. sp. was found in soil around birch (Betula papyrifera Marsh.) in the forest near Aylen Lake, Ontario, Canada. It is distinguished from other species in that it has a robust body, a markedly reduced postvulval diameter, an ovary usually with double reflexure at the distal end, a spermagonium, and a spear 58 to 73 microns (μ) long.

Paratylenchus tateae n. sp. was found in soil samples collected from around corn, alfalfa, and clover in Ontario. The spear is 15 to 16.8 μ long, the head offset and truncate. The lateral lips are larger than the subdorsal and subventral lips. The tail terminus is pointed to conically round.

Criconema seymouri n. sp. was collected from Mt. Seymour, near Vancouver, British Columbia, from soil under a cedar tree (Thuja plicata Donn) August 22, 1962. It is close to Criconema tenuicaudatum Siddiqi, 1961 and CriGonema hungaruum Andrhssy, 1962. It differs from both species in having a much shorter spear, and in having the location of the excretory pore more anterior. In a collection from Mt. Seymour, near Vancouver, British Columbia, three females and a number of males of Criconema were found in soil from under a cedar tree. These represent a new species, and this is described here as Criconema seymouri.

Paratylenchus veruculatus n. sp. was collected by Mrs. John Darroch of Woodstock, New Brunswick, Canada, from soil around roots of heather from Scotland in 1961. This species has characters close to P. microdorus and P. brevihastus, but it is a smaller species. It also differs from P. microdorus in having slightly coarser body annulation, base of spear not conical, spear slightly shorter, and males present. It differs from P. brevihastus in that the male has a median esophageal bulb, a spear is present, and the spicule is shorter; in the female, the spear is shorter also; tip of tail with a great variation of shape and pointed tip is common.

Male and female specimens of Paratylenchus brevihastus n. sp. were collected in Ontario, Canada, from soil around the roots of blue violets (Viola cucullata Ait.) and grass, alfalfa (Medicago sativa L.), oats (Avena sp.), and red clover (Trifolium pratense L.) during 1958 to 1961. This species has characters close to those of Paratylenchus microdorus, but differs from it in having spear knobs with rather flat anterior surfaces and front of lip region with truncate appearance. Males present.

A new species of Dactylotylenchus, D. filiformis, was described and more information for D. crassacuticulus Wu, 1968 was presented. The thick cuticle and the digitate sclerotized labial framework of this genus provide the unique character for Dactylotylenchus in the family Tylenchidae. A new subfamily Dactylotylenchinae was created to accommodate this genus.

Anguina calamagrostis n. sp., found infesting bluejoint grass, Calamagrostis canadensis (Michx.) Nutt., from Canada is described. The name "crustaformeria" is proposed for the region of the reproductive system immediately behind the spermatheca and where the egg shell is formed. The generic characters for the genera Anguina and Ditylenchus are emended, based on the difference in the morphology of the crustaformeria.

Pratylenchus macrostylus n. sp. was found in soil samples collected from around trees in Algonquin Park and Aylen Lake, Ontario, and in Stanley Park, Vancouver, British Columbia, Canada. It has the longest spear in the genus, usually 22 to 24 μ long, with the spear knob flattened on the anterior surface, the lip region roundly convex, generally with two annules. The labial framework is strongly arched and extends into two body annules. The tail is usually conically rounded with variations and the postuterine branch has a vestigial ovary.