NO. 1892. A NEW PARASITIC NEMATODE— RANSOM AND HALL. 



177 



rays diverge considerably, which is unusual in the genus Osteriagia, 

 and their tips arc at least half as far apart as the tips of the latero- 

 ventral and externo-lateral rays. The distance between the tips 

 of the externo-lateral and medio-lateral rays is much less than that 

 between the latter and the tip of the 

 ])ostero-lateral ray. Of the paired 

 rays, the late ro-ventral is the thickest- 

 FolloA\dng this in the order of size are 



Imm. 



Imm. 



1.— OSTERTAGU BULLOSA. MALE AND 

 FEMALE. *VULVA. ENLARGED. 



lOOyU. 



the externo-lateral (fig. 2, e. I.), 

 then the medio-lateral (fig. 2, 

 m. I.), the postero-lateral (fig. 

 2, p. I.), and the externo- dorsal 

 (fig. 2, e. d.), which are of about 

 the same size, and lastly the 

 ventro-ventral. The dorsal ray 

 (fig. 2, d.) is about 140 // long 

 and is bifurcated 25 to 40 /t 

 from its posterior end. The 

 terminal branches have each a 

 small branch, sometimes re- 

 duced to a mere knob, on the 

 outer side. At times each of the 

 terminal branches ends in a very 

 small fork and at times appears to end \v'ithout forking. The spicules 

 (fig. 2, sp.) are 140 to 180 ;« long and 15 to 20 /t wide at the anterior 

 end. They gradually narrow toward the posterior end, which is 

 pointed, and do not fork. Usually the tips are curved but in some 

 20441°— rroc.N.M.vol.42— 12 12 



Fig. 2.— Ostertagia buli.o.sa. Posterior end of 



BODY OF male, vmWED FROM LEFT SIDE. buL, PREBUR- 



sal bulla; d., dorsal ray; c. d., externo-dorsal 



ray; e. I., EXTERNO-LATERAL RAY; gUh., GUBERNACU- 

 LUM; /. v., LATERO-VENTRAL RAY; TTJ. Z., MEDIO-LATERAL 

 ray; p. /., POSTERO-L.\TERAL RAY; *p., LEFT SPICULE; 

 V. v., VENTRO-VENTRAL RAY. ENLARGED. 



