TRICHOSTRONGYLIN.E 



269 



nv.l. 



Fig. 136. — Hsemonchus contortus, — enlarged, 

 Posterior extremity of male, dorsal Aaew; d. 

 dorsal ray supporting the asymmetrically 

 situated dorsal lobe of bursa; e. d., externo- 

 dorsal ray; e. 1., externo-lateral ray; gub., 

 gubernaculum; 1. v., latero-ventral ray; m. 1., 

 medio-lateral ray; p. 1., postero-lateral ray; 

 sp., spicule; v. v., ventro-vcntral ray (after 

 Ransom, Bull. No. 127, Bureau An. Ind., U. S. 

 Fig. 134.— l:S::^^}^m, Dept. Agr.). 



Hsemonchus con- i c c i i / / 



tortus, female. Fig. i35.-Ha5mon- Length oi tcniale, about 6 mm. (1/4 

 *Vuiva. x5. (Af- chus contortus, an- of an inch); male about 5 mm. (3/16 



ter Ransom, Bull, terior portion of 



No. 127, Bu 

 An. Ind., U. S 

 Dept. Agr.). 



body, — enlarged: c. 

 p., cervical papilla; 

 es., esophagus; int., 

 intestine; n. r., nerve 

 ring (after Ransom, 

 Bull. No. 127, Bu. 

 An. Ind., U. S. Dept. 

 Agr.). 



of an inch). 



The eggs are oval, 63-70 microns in 

 length by 30-32 microns in width, seg- 

 mented at time of deposition. 



The worm is parasitic in the small 

 intestine, more rarely the abomasum, 

 of the sheep and goat. 

 3. Ostertagia marshalli. Fig. 139. Trichostrongylinae (p. 268). — 

 The mouth is small and surrounded b\' six indistinct papillae. The 

 cuticle has twenty-five to thirty-five longitudinal ridges appearing as 

 lines. Cervical papillae 340-415 microns from anterior end of the body. 

 The bursa of the male is bilobate; spicules short and similar, yellowish 

 brown in color. The tail of the female is slender, gradually tapering, 

 and rounded at the tip. The \ailva is a transverse slit located near the 

 tail extremitv. 



