OXYURIS YBEMIOULABIS. 367 



Walter, and Eberth. Probably aU that may be said with certainty 

 is tbat a pale band, forming the oesophageal ring, exists a little 

 below the mouth, and from this ring several fine filaments pass 

 off in different directions, and stand connected, more or less con- 

 spicuously, in their course, with numerous large granular cells, 

 which are confidently affirmed to be ganghonic in their character. 



Fortunately, one can speak a little more precisely as regards 

 the digestive system. In the centre of the space occupied by the 

 large external lateral vesicular expansions, one perceives three 

 well-marked oral papillae, which can be withdrawn so as to leave 

 the oral opening rounded and simple. The mouth communicates 

 directly with an elongated, club-shaped oesophagus, which, though 

 cyhndrical in the mass, encloses a central triquetrous canal. A 

 sudden constriction of the cylinder leads to the formation of a 

 strong spherical CBSophageal bulb, which Kiichenmeister has com- 

 pared to a gizzard, because the interior of it is occupied by a 

 peculiar valvular apparatus. These tooth-like, crushing organs, 

 however, are by no means uncommon in other nematodes. Imme- 

 diately below the bulb, the true stomach makes its appearance in 

 the form of a club-shaped mass, which insensibly merges into the 

 intestinal canal, the latter again widening a little in front of the 

 anal orifice. 



The reproductive organs, in the male, consist of a simple cylin- 

 drical testicular tube, which is folded upon itself at the upper 

 part, and terminates below in a cloacal cavity common to it and 

 the intestinal tube. It is furnished with a small retractile infundi- 

 buliform penis or spiculum, which is shghtly curved and imper- 

 forate. In the female the generative organs comprise a short 

 utero-vaginal canal, two very broad uterine horns, which, in the 

 sexuaUy-mature condition are so crowded with eggs that they 

 frequently obscure all the other neighbouring parts, and two 

 narrow ovarian coecal filaments, in which the germs and granular 

 yelk are formed. The vaginal opening is simple, and, like that of 

 the intestine, is placed on one and the same side of the body ; the 



