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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 50. 



striated. The bursa is apparently not deeply incised dorsally. The 

 rays are arranged as given in the generic diagnosis. The medio- 

 lateral and externo-lateral rays are the largest. The 

 spicules (fig. 186) are 360 /x long and are bifurcated 

 70 fjL from the proximal end. The proximal end is 

 cup-shaped and is 35 /x in diameter. 



Female imknown. 



Host. — Citellus elegans. 



Location. — Small intestine. 



Locality. — Waldon, Colorado. 



Type material.— ^o. 16176, U.S.N.M. (Bureau of 

 Animal Industry helminthological collection). 



The single male on which this species is described 

 was collected from alcoholic host material collected by 

 Messrs. E. K. Warren and H. E. Durand. 



WARRENIUS Hall, 1916, new genus. 



Generic diagnosis. — Trichostrongylinae (p. 123) : 

 Head simple, no lips eA^dent. Cuticle of head in- 

 flated. Unilateral cervical wing present (fig. 187). 

 The bursa is deeply incised dorsally to form 2 large 

 lateral lobes and a small, but distinct dorsal lobe. 

 The dorsal, lateral, and ventral ray systems are well 

 defined and separated from one another, the rays of 

 each system being more closely related to one another 

 than to rays of other systems. The dorsal lobe is sup- 

 ported by the dorsal ray Avhich sends out a short 

 branch to each side almost two-thirds of its length 

 from its proximal end and then branches to form two 

 longer terminal branches (fig. 188). The externo- 

 dorsal rays are long w\avy rays lying in the lateral 

 lobes and ending in curved termina- 

 tions, the tips of which are farther 

 from the bursa margin than are points farther back 

 along the rays. The recurved tip turns toward the 

 dorsal ray and is closer to this than to the postero- 

 lateral. The postero-lateral and medio-lateral rays 

 originate in a connuon stem (fig. 189). The postero- 

 lateral turns back toward the externo-dorsal and 

 terminates a short distance from the bursa margin. 

 The medio-lateral proceeds direct to a point on the 

 bursa margin, and the externo-lateral, which origi- 

 nates from the common trimk of the postero-lateral 

 and medio-lateral, also proceeds practically straight 



Fig. 186.— Citel- 

 i.inema bifur- 

 CATUM. Spic- 

 ules. X 300. 



to the bursa nuirgin. The latero- ventral and ventro- 



FlG. 187.— WAR- 

 RENIUS QUAD- 



Erv'iTTATi. An- 

 terior EX- 

 TREMITY. X 



300. 



