Description and figures are presented for the following species and subspecies, which the writer considers should constitute the genus Streptocara: S. crassicauda crassicauda (Creplin, 1829), S. crassicauda longispiculata n. subsp., S. californica (Gedoelst, 1919), S. formosensis Sugimoto, 1930, S. incognita n. sp., and S. recta (Linstow, 1879). Host-lists and data on prevalence in birds, mainly waterfowl, from British Columbia, Canada, are given for these species and Paracuaria tridentata (Linstow, 1877). Yamaguti's 1961 list of species of Streptocara is examined critically; some of the modifications suggested in the literature since 1961 are accepted, and the following changes proposed: S. cirrohamata (Linstow, 1888) to Ingliseria cirrohamata (Linstow, 1888) new genus, new combination; S. triaenucha (Wright, 1879) to Synhimantus (D.) triaenucha (Wright, 1879) n. comb. (syn. S. (D.) canadensis Mawson, 1956); and S. somateriae Ryzhikov, 1960 to synonymy with S. formosensis Sugimoto, 1930.

Twenty-nine grizzly bears, Ursus arctos L., killed between 1965 and 1967 in northwestern Canada, principally the Yukon Territory, were examined for helminths. The authors found six species of helminths with the following prevalence: Baylisascaris transfuga (Rudolphi, 1819) Sprent, 1968 in 16 of 21 bears; Dochmoides yukonensis Wolfgang, 1956 in 10 of 21; Dirofilaria ursi Yamaguti, 1941 in 3 of 27; Trichnella spiralis (Owen, 1835) Railliet, 1896 in21 of 24; Diphyllobolhrium (?) ursi Rausch, 1954 provis. in 3 of 21; and Taenia krabbei Moniez, 1879 in 2 of 21 bears. These findings are discussed in the light of other reports, and constitute the first record of helminths from grizzly bears in Canada.

Wolves from the Yukon and Northwest Territories harbored the following gastrointestinal helminths: Alaria americana (10 of 171), A. arisaemoides (2/171), Diphyllobothrium sp, (1/171). Mesocestoidcs kirbyi (3/171), Taenia hydatigena (54/111), T. krabbei (63/111), T. pisiformis (2/111), T. serialis (41/111), Echinococcus granulosus (24/171), Toxascaris leonina (83/171). Uncinaria stenocephala (11/171), Spirocerca arctica (1/171), and S. lupi (1/171). Larval Trichinella spiralis occurred in 72 of 153 diaphragms. A. arisaemoides, M. kirbyi, and S. arctica were found for the first time in Canis lupus, while S. lupi, S. arctica, and the prevalence of T. spiralis in wolves are reported for the first time in Canada.

A. bendelli n. sp. differs from the others of the genus in that its dentate cephalic quadrants join laterally producing a bipartite rather than quadripartite appearance. It can be recognized also by its combination of large dentiform processes, long vestibule, short glandular oesophagus, and 9–14 pairs of preanal papillae; no other species parasitizes an obligate terrestrial host. The following species composition is proposed for Ancyracanthopsis Diesing, 1861: A. bilabiata (Molin, 1860) A. coronata (Molin, 1860); A. madagascariensis Kung, 1948; A. petrovi Guschanskaya, 1950; (?)A. parvialata (Belopolskaya, 1953); A. gallinulae (Wang, 1966) n. comb.; and A. bendelli n. sp. It is concluded that A. quadripartita (Clapham, 1945) and A. schikhobalovi Guschanskaya, 1950 are synonyms of A. coronata, and that Skrjabinobronema sinica Wang, 1966 is a synonym of A. madagascariensis. Specimens of Sciadiocara umbellifera (Molin, I860) (Syn: S. legendrei Petter, 1967) from British Columbia possess minute serrations along the posterior edges of the cephalic lappets. Viktorocara limosae Mawson, 1968 is considered a synonym of V. limosae Daiya, 1966. Stellocaronema Gilbert, 1930 should contain S. skrjabini Gilbert, 1930 (Syn: S, glareolae Mawson, 1968) and S. fausti (Li, 1934) n. comb, (Syn: Stellocaronema buckleyi Sarwar, 1956); S, charadrii Mawson, 1968 probably represents a new genus. New records are A. coronata from Actitis macularia and Seiurus noveboracensis in British Columbia and from Cassidix mexicanus in Mexico; V. limosae from Erolia alpina; and S. skrjabini from E. alpina, Ereunetes mauri, and Crocethia alba in British Columbia.

In St. Lawrence River marshes, fatal sporadic and epizootic typhlitis in breeding populations of black ducks, Anas rubripes; blue-winged teal, A. discors; and migrant green-winged teal, A. carolinensis, is attributed to Cyathocotyle bushiensis Khan, 1962. This is the first report of C. bushiensis in natural definitive hosts, and the first record of the genus Cyathocotyle in North America. Pathogenicity of C. bushiensis was confirmed experimentally by using metacercariae from the most abundant local gastropod, Bythinia tentaculata, to produce cyathocotyliasis in Pekin ducklings.