42 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 50. 



ascarids with interlabia, such as the well-known forms from seals. 

 However, I am disinclined to put this species in the genus Kathleena. 

 There is no reason to think that tlie esophageal appendage and in- 

 testinal ceca are present and the host animals are from widely sepa- 

 rated groups. On the other hand, I was surprised to find that a para- 

 site I had regarded on first sight and after some examination as a 

 species of Ascaris, perhaps close to Ascaris pigmentata, was a 

 species of Protosfirura. The gross appearance of the animal, the 

 size and other external characteristics spoke for its ascarid nature, 

 but it was, nevertheless, not even in the same superfamily as the 

 ascarids. In view of this fact, I have left Leidy's and von Linstow's 

 species in the genus Ascai^is, not on the grounds that they belong 

 there, but for fear they may prove to be separated more than gen- 

 erically from that genus. 



Genus CROSSOPHORUS Hemprich and Ehrenberg, 1828. 



Synonym. — Ascans of Schneider, 1806, in part. 



Generic diagnosis. — Ascarinae (p. 39) : Head with three lips hol- 

 lowed on the inside and provided with papillae or fringed. In- 

 testine with two ceca directed anteriorly. Male with a, simple spicule. 

 Female uterus with two branches. 



Type-species. — Crossophorus colluris Hemprich and Ehrenberg, 

 1828. 



ANALYTICAL KEY TO SPECIKS OF CKOSSOPIIORUS. 



1. Head separated from body by pronounced strangulation and surrounded by a 



collar of bifurcated fimbriae Crossopliorus collaris, p. 42. 



Head not shai-ply separated from body and without collar of fimbriae ; each 

 lip provided with 3 long tentacles Crossophorus tentaculatus, p. 43. 



CROSSOPHORUS COLLARIS Hemprich and Ehren- 

 berg, 1828. 



/Synonym. — Ascaris ferox Schneider, 

 1866. 



- Specif c diagnosis. — C 7'os s op horus 

 (p. 42) : Lips (figs. 47 and 48) very simi- 

 lar, semicircular with scalloped edge. The 

 dental ridge is interrupted, forming on 

 the outer edge of the lip on each side five 

 combs of spines, the number of spines fig- 

 ured as two to eight to a comb. An unin- 

 FiG. 47.— Crossophorus COLLARIS. terrupted row of spines encircles the lips, 

 i'„Tsce»Br;.,",« "'"■ proceeding in a bow to the inner s„r- 



face of the base of each lip, bending about 

 and crossing the outer basis of the lip, going back to the body cuticle 

 parallel to the posterior edge of the lip, and proceeding again to the 



