356 ANIMAL PARASITES. 



peculiar genus of the Nematoda separated from Ascaris, and give 

 the following description especially from Dujardin. 



Corpus cylindricum aut fere fusiforme, sublongum, in feminis 

 retrorsum subulatum ; caput inerme ; os rotundum (in stalu con- 

 tractionis) aut triangulare (in statu actionis), trilabiatum ; oeso- 

 phagus musculosus, cylindricus aut claviformis et canali triquetro 

 perforates ; ventriculus globosus cavitate triangulari ; intestinum in 

 feminis ante apicem cauda acutce, in maribus in centro cauda 

 apertum. 



Mares ; fere microscopici ; plerumque spirales in fine pos- 

 teriore obtusi ; penis simplex, uncinatus. 



Femince : cauda acuta ; vagina semper in parte vermis anteriore 

 sita ; uterus bilocularis cum ovariis 2. Ovula l&via, oblonga, non 

 symmetrica y multo longiora ) quam latiora omnino magna : 0'064 

 mill, ad 0*136 longa. 



1. Oxyuris vermicularis (Bremser, Deslongchamps, Dujardin, 

 Von Siebold). 



Synon. ; Ascaris vermicularis (Linne; Goeze; Rudolphi; 

 Schmalz ; Creplin ; Diesing) ; Fusaria vermicularis (Zeder) 

 = Kinder-, Mastdarm-, Madenwurm = Arschmade = Aarsmade 

 = Darmschabe = Smaa Spolorme = Borncorm = Barnmask = Bots 

 (Thread-worms). 



Bremser first separated this worm from the Ascarides, and 

 certainly with perfect justice, notwithstanding the great au- 

 thorities opposed to him. I place the worm as an Oxyuris, 

 partly for the reasons already given by Dujardin, because 

 oesophagus and pharynx are triangular, and the mouth is some- 

 times round, sometimes triangular, according to the degree of its 

 contraction; because the lateral, wing-shaped appendages at the 

 mouth are simply a uniform inflation of the head, and no true 

 membranous wings ; and because there are only three lips to the 

 mouth ; and partly on account of the nature of the male, which 

 Dujardin himself never appears to have seen. The males are very 

 much smaller than the females, as is usually the case with the 

 males of the true Ascarides. Then the caudal extremity of the 

 male Ascarides usually forms a small face resembling the leaf of 

 Sagittaria sagittifolia, whilst the caudal extremity of Oxyuris 

 vermicularis presents a round surface, which is capable of taking 

 the form of a sucking surface. But, in the last place, the simple 



