HELIGMOSOMINAE 191 



This genus is insufficiently characterized. Travassos (1921, 

 Mem. Inst. Oswaldo Cruz, xiii, 104) considers that C. bifur- 

 catum much resembles Viannella fariai Travassos. It is 

 possible that Citellinema and Viannella are synonymous, but 

 the point cannot be decided until Hall's species is redescribed. 



10. Warrenius HaU, 1916. 



Cuticle of head inflated. A short, unilateral cervical ala 

 present. Bursa of male deeply incised ventrally to form two 

 large lateral lobes and a small, distinct dorsal lobe. Ventral 

 rays divergent, unusually long and thick. Postero-lateral 

 and medio-lateral rays arise from a common trunk, but are 

 separated distally. Externo-dorsal rays originate from the 

 median dorsal stem near its base and are relatively long and 

 slender. Dorsal ray small, with a pair of short accessory 

 branches just in front of its terminal bifurcation. Spicules 

 long and slender. Female unknown. 



Hab. Intestine of a Rodent (one species known). 

 Genotype : W . quadrivittati Hall, 1916. 



HaU, 1916, Proc. U.S. Nat. Mus., 1, 123, 142 ; Travassos, 

 1921, Mem. Inst. Oswaldo Cruz, Rio de Janeiro, xiii, 103. 



Travassos (1921) considers that the presence of a cervical 

 ala is probably an artefact brought about during preserva- 

 tion. He suggests that W. quadrivittati closely resembles 

 Heligmosomum aculeatum and H. nematodiriforme and ought 

 perhaps to be included in the genus Heligmosomum. As in 

 the case of Citellinema, only a fuller description can establish 

 the validity of Hall's genus. 



11. Ollulanus Leuckart, 1865. 



i- A minute form, with the anterior end generally coiled upon 

 itself. The cuticle of the anterior end is invaginated to form 

 a very small, subspherical buccal cavity. Large cervical 

 papillae present. Bursa without distinct dorsal lobe or mid- 

 dorsal incision. Ventral rays separate but parallel. Antero- 

 lateral ray much thicker than, but parallel to, the remaining 

 lateral rays. Externo-dorsal rays originate from the median 

 stem of the dorsal ray at about its middle. Dorsal ray 

 comparatively stout, bifurcate distally. Spicules bifurcate 

 distally, one termination being rounded, the other acutely 

 pointed. Accessory piece absent. Tail of female truncate, 

 typically with three terminal cusps or spines, but occasionally 

 with two additional cusps. Vulva at about the beginning of 

 the posterior sixth of the body. Eggs large and few. Mature 

 females with from one to three very large larvae in the 

 body. 



