170 STRONGYLOIDEA 



Molin, 1861, Mem. R. 1st. Veneto, ix, 436, 534; Railliet, 

 1902, Compf. rend. Soc. Biol., Paris, liv, 109; Alessandrini, 



1909, Arch. Parasitol., Paris, xiii, 459; Lane, 1923, Parasitol., 

 XV, 358; Cameron, 1924, Journ. Helminthol., ii, 65. 



We have placed this genus in the subfamily Necatorinae 

 on account of its general resemblances to the other members 

 of that group. Although the ventral cutting-plates charac- 

 teristic of the groujj are apparently absent, the general structure 

 of the buccal capsule and the form of the bursal rays suggest 

 its inclusion here. 



4. Bunostomum Railliet, 1902. 

 Syn. Monodontus Molin, 1861, e. p. {= Monodontus Ran- 

 som, 1911, Cameron, 1923); Bustomum Lane, 1917. 



Anterior end bent dorsally. Mouth guarded by a pair of 

 ventral cutting-plates. Buccal capsule large, infundibular. 

 Towards its base a strong dorsal tooth along which runs the 

 dorsal gutter, and two or four smaller ventral lancets. Bursa 

 with an asymmetrical dorsal lobe. The right externo-dorsal 

 ray arises high up on the main dorsal stem, and is long and 

 slender. The left externo-dorsal ray is much shorter, arising 

 at about the level of the bifurcation of the dorsal ray. Ter- 

 minations of dorsal ray tridigitate. Spicules slender, not 

 barbed. Vulva a little in front of the middle of the body. 

 Uterine branches opposed. 



Hab. Small intestine of Ruminants. 



Genotjrpe : B. [Strongi/lus] trigonocephalum (Rudolphi, 

 1808). 



Rudolphi, 1808, Entozoorum . . . Historia naturalis, i, 

 PI. II, figs. 5-6; Molin, 1861, Mem. R. 1st. Veneto, ix, 435, 

 463; Railliet, 1902, Com2)t. rend. Soc. Biol, Paris, liv, 108; 



1910, Bull. Soc. Path, exot., Paris, iii, 312; Ransom, 1911, 

 U.S. Dept. Agric, Bur. Anim. Indust. Bull. 127, 27, 124; 

 Lane, 1917, Ind. Journ. Med. Res., iv, 414; Cameron, 1923, 

 Journ. Helminthol., i, 99. 



Railliet (1902) proposed the genus Bunostomum, with 

 B. trigonocephahim as type, to replace Monodontus Molin, 

 1861, on account of the existence of earlier, very similar, 

 generic names. There may be no justification for Railliet's 

 proposal, but, as Ransom (1911) pointed out, if it is shown 

 that M. semicircularis Molin, 1861, and M. trigonocephalus 

 are not congeneric, then the genus Bunostomum, with the 

 latter species as its tjrpe, must be retained. The two species 

 mentioned are certainly not congeneric, and therefore the 

 genus Bunostomum stands. 



Cameron (1923) considers that the statement of Railliet 

 (1895) that Molin had made B. trigonocephahim the type of 



