420 On a new Trichostrongyle Genus. 
together with the presence of two ovaries &c. in the female, 
place it in. the subfamily Trichostrongyline, Leiper, 1908. 
This parasite differs widely from all known ‘Trichostrongyle 
genera, its closest relation possibly being Cooperia, Ransom, 
1907. It, however, differs from Cooperia in several respects, 
more especially in the shape of the dorsal ray and the relative 
thicknesses of the lateral rays of the bursa. The position of 
the vulva in this parasite is also quite different, in being 
placed much further back than in Cooperia. 
I propose to designate this parasite as type-species of a 
new genus 
TRICHOHELIX, gen. nov., 
of which the following may be taken as the chief characters :— 
Trichostrongylinee. Body red and spirally coiled. Head 
round and thick, about 35 w in diameter. Cuticle round 
head inflated to form a vesicular swelling, limited behind 
by a deep constriction encircling the neck. Rest of the 
cuticle strikingly inflated and showing marked transverse 
striations only on the anterior half of the ventral surface. 
Longitudinal striations faint. Lateral ale absent. Cervical 
papille absent. Male bursa indistinctly trilobate. Dorsal 
ray stout, bifurcate, and its tips are tripartite. Tip of medio- 
Jateral ray sharply recurved. Ventro-ventral ray strongly 
arched forwards and inwards. Spicules straight, tubular, 
equal, and of medium size; they are branched posteriorly. 
Gubernaculum present. Prebursal papillee absent. Vulva 
situated slightly in front of the anus. Ovijectors well deve- 
loped and divergent. Uteri parallel. Hggs large, oval, and 
thin-shelled, measuring over 100 w in length. 
Type-species, 7richohelix tuberculata, Par. & Stoss., 1901. 
REFERENCES. 
Hau, M.C. 1916. “Nematode Parasites of the Orders Rodentia, 
Lagomorpha, and Hyracoidea.” Proc. U.S. Nat. Mus. vol. 1. 
no, 2181. Washington. 
Lerrrr, R. T. 1908. ‘An Account of some Helminthes collected in 
Sudan.” Third Report of the Wellcome Research Laboratories, 
pp. 189-191. Ihartoum. 
Linstow, 0. von. 1878. Compendium der Helminthologie, Hannover. 
1889. Compendium der Helminthologie, Nachtrag. Hannover. 
Moun, R. 1861. 1 sottordine degli Acrofalli. Venice. 
Parona, C., and Srosstcu, M. 1901. “ Qsophagostomum tubercu- 
latum, n. sp., parasita dei Dasypus.” Boll. d. Mus. d. Zool. e 
Anat. Comp. d. R. Univ. d. Genova, no. 110. 
Ransom, B.H. 1911. “The Nematodes parasitic in the Alimentary 
Tract of Cattle, Sheep, and other Ruminants.” U.S. Dep. of Agric., 
sureau of Anim. Ind. Bull. 127, Washington. 
