OXYURIS. 355 



longum, 019 mill, vel I'" ad basin latum; truncus 27 mill, vel 

 7 — 8'" longus, 0*78 mill, vel §"' latus ; extremitate caudali obtusa ; 

 penis vagina cylindrica, tubulosa, 1-55 mill, longa, O07 mill, lata, 

 spinis parvulis aut lamellis triangular thus, retroversis, 0*005 mill, 

 longis armata, antice dilatata ; penis simplex, 6' 75 mill, longus ; 

 0025 mill, ad 0038 mill, latus, cum lamella pellucida instructus. 



Femina : 60 — 70 mill. v. 24'" longa ; collum 42 — 49 mill, 

 v. 18'" et I'" latum; truncus 18—21 mill. v. 6'"; 0'94 mill, 

 aut v. §'" lata ; subrecta vel parum curvata ; cauda obtusa ; ovula 

 navicularia, 0061 mill, longa ; in ovulorum extremitatibus duo 

 nodule pellucidi magnitudinis 0008 mill., unde longitudo totalis 

 0077 mill. 



Its usual locality is almost exclusively the caecum of the 

 ruminants. The characteristic mark of the species is the consi- 

 derable length of the penis and its sheath. 



II. Oxyuris. 



As we have already seen to be the case with the name of 

 whip-worm (Peitschenwurm) for the Trichocephalus, so is it here 

 with the Greek name first introduced by Rudolphi. The deno- 

 mination Oxyuris = Sharp-tail (from o^vg and ovpa) only applies 

 to the female, but by no means to the male. 



The worm is placed by Dujardin as the 16th genus of the 

 first class of the Helmintha ; that is to say, the Nematoda. 

 Diesing has separated it from his Oxyurides, and placed it with 

 the Ascarides. Thus, whilst he treats of the Oxyurides, in the 

 Order VI, Nematoidea ; Suborder II, Proctucha ; Tribe III, 

 Gamonematoidea ; Section I, Hypophalli (penis infra extremitatem 

 caudalem), as Genus XVIII (corpus capil/are, extremitate caudali 

 maris subrecta, alata vel exalata ; pene in vagina bipartita. Os 

 orbiculare), he has placed the Oxyuris vermicularis in the same 

 tribe and section as Genus XX, Ascaris ; A, Gymnoascaridre 

 (corpus inerme) ; Division I, Apterocephalce (caput non alatum) ; 

 Subdivision I, Oxycercce, (a) macrura.', (a) caput epidermide inflata, 

 1, Ascaris vermicularis. The introduction of a vox hybrida like 

 Oxycerca is enough of itself to make this above all measure 

 artificial classification, appear but little acceptable. With 

 Dujardin and most other authors, we treat the Oxyurides as a 



