NO. 2131. 



NEMATODE PARASITES OF RODMfS—HALL. 



^3 



argue against this. One specimen is 10.5 mm. long, of which the 

 anterior esophageal portion is 6.88 mm., while the other specimen 

 is 8.6 mm. long, of which the anterior esophageal portion is 6 mm. 



Host. — ThomoTiiys fossor. 



Location. — Cecum. 



Locality. — Crested Bnttes, Colorado, and Livermore, Colorado. 



Type material.— Q^i. No. 16179, U.S.N.M. (Bureau of Animal 

 Industry helminthological collection). 



These specimens were collected by the writer from alcoholic 

 material collected by Mr. E. R. Warren, of Colorado Springs, and 

 were reported by the writer in 1912 in a list of parasites from 

 Colorado. 



TRICHURIS GRACILIS (Rudolphi, 1819) Hall, 1916. 



Synonym. — Trichoccphalus gracilis Rudolphi, 1819. 



Specif. c diagnosis. — Trichuris (p. 20) : Whitish, capillary portion 

 darkening anteriorly. Head acute. Anterior esophageal portion of 

 body scarcely longer than posterior portion. 



Male unloiown. 



Female 47 to 54 mm. long. Posterior portion of body relatively 

 slender, slightly curved, blunt posteriorly. 



Host. — Dasyprocta aguti {Cavia agouti). 



Location. — Cecum. 



Locality. — Brazil. 



TRICHURIS INFUNDIEULUS (von Linstow, 1906) Hall, 1916. 



Synonym. — Trichocephalus infundibulus von Linstow, 190G. 



Specif c diagnosis. — Tricliurls (p. 20) : Diameter of bacillary band 

 equals two-thirds of the 

 diameter of body. 



Male 44.6 mm. long wdth 

 a maximum thickness of 

 790 t/.. Ratio of length of 

 anterior esophageal portion 

 of body to length of pos- 

 terior portion is 7:6. Spi- 

 cule 1.94 mm. long and 26 

 ix thick, gradually thinning 

 to a point posteriorly. The 

 sheath has transverse folds 

 at its base and widens in a 

 funnel opening posteriorly 

 {fig. 21). (These folds may be transient rather than constant.) It is 

 studded with little shining cones of equal size, set close together and 

 directed posteriorly. The posterior body is in two parts. (This last 



Fig. 21.— Trichuris iNFtJNBiBULu.s. Posteriorextremitt 

 OF MALE. Enlarged. After von Linstow, 1906. 



