1G4 THE FUR SEALS OF THE PRIBILOF ISLANDS. 



As Steller's sea cow is uow extinct it can never be denionstratod what species 

 Steller found. The names A. rytiuae and A. rhytinae may, thereiore, be buried, and 

 all time used in speculating as to tlie affinities of this worm with corresponding- jiara- 

 sites in other hosts may be considei-ed lost. 



14. "ASCARIS CAPSULARIA. ' 



Ascaris capsularia is a name applied to immature nematodes, supposed to be 

 ascarides, and found in fish. NuTuerous supposed species have been separated under 

 distinct specitic names, generally taken from the names of the hosts, the generic names 

 Agamoneina, Nematoidcum, or Ascaris being used by various authors. Personally, we 

 mnst confess our inability to distinguish at present these numerous forms from each 

 other or to determine from the published descriptions of the worms which forms should 

 be considered synonyms, which forms should be looked upon as distinct, and which 

 forms should be associated with tliis, that, or the other adult Ascaris. We do not deny 

 that other authors are correct in their interpretations of these larval worms, but we 

 would suggest that a thorough study of the exact food habits of fish-eating mammals 

 in connection with this subject would aid in solving the problem of the life history of 

 many of these parasites. 



III.— Family STRONGYLIDAE. 



Diagnosis. — Neuiatoda witb lioily elongate, cylindvical, r;irel.v filiform. Month is probably 

 always provided with six papillae, of which the four siibmcdiaii are gein-ially salient iu form of nodules 

 or conical points. In some cases the mouth is in the a.\is of the body; in others, turned dorsMlly or 

 ventrally. and occasionally provided with a chitinous arniature. Oesophagus more or les.s swollen in 

 posterior portion, but without forming a distinct oesophageal bulb. M;iles ]irovided with a caudal 

 hunsa, open or closed, entire or divided, with one or two spicules. Females with one or two ovaries; 

 vulva anterior or posterior to middle, in some cases near the anus. Eggs deposited during segmenta- 

 tion, in some cases containing embryo. 



Tyi)e: Strongylus, O. F. Miiller. 



Sulslamily SCI^KROSTOIMIN^H:;. 



Diagnosis. — Strongylidae; meroniyaria; month with more or less complete chitinous armature. 

 Male with two c(iual sjiiculcs; caudal bursa with rays, the posteromedian and postero-external being 

 united iu a common liase. Female with two ovaries, except in (Jlliilaniis. 

 Type: Sclerostoma, Blainville, 1828. 



Genus UNCINARIA Frolich, 1789. 



1789, Uncinaria Frolich, Der Naturforscher, XXIV, jip. 1.37-13!). Type, Uncinaria valpis Frolich, 1789. 

 ISiSjAgchylostoma DuitiNi, Auual. univers. di medic. Miliiuo, CVI, April, pp. 5-13. Type, AiirhyJox- 



loina diiodenale Dubiui, 1813. 

 1845, Ancijloaloma Cheplin, Arehiv. f. Nnturg., 11 ,)hg., I, p. 325. For .l<iclujlostoma Dubini, 1843. 

 1845, Dochmiiis Dujaudin, Histoire natiirello d. helminthes, i)p. 267-275. Typo, Dochmiun triijoiiocci>h- 



alits (Kudolphi, 1809) = Uncinaria vulpis Frolich, 1789. 

 (1846), Anchijlostotiia Delle Ciiiaje Reudicon. dell Accad. delle Sci. Najjoli, V, p. 339. 

 1851, Anchylostomiim DiESiN<i, Systema helminthum, II, \>. 321-322. For Agchylosioma Dubini, 1^3. 

 1855, Ancylostomum KCichknmeister, Di(- in und auf d. Kfirper d. lebenden Menschen vorkoninieud. 



Parasiten, I, p. 297. 

 1861, Monodontus MoLiN [nee Monodunta Lamarck, 1799], II Sottordiue degli Acrolalli, i>p. 11-43. 



Type, M. semicircularia Molin, 1861. 

 Diagnosis. — Sclerestominao with anterior extremity curved dorsally; mouth round to oval, open- 

 in"- obli(iuely, limited by a transparent border and followed by achitinous buccal capsule; the dorsal 

 portion of the capsule is shorter than the ventral, and is supported by a conical structure the point 

 of which sometimes extends into the cavity; ventral at the base of the buccal capsule are found two 



