STUDIES ON THE ECTOPAEASITIC TBEMATODES OF JAP AX. 129 



membranous wall is exceedingly thick, and its internal surface is 

 uniformly covered with stout cilia. The terminal half of the vaginal 

 canal is, in this genus, surrounded by numerous unicellular glands, the 

 vaginal glands. Since I had only a single specimen of the worm and 

 was therefore compelled to pass and repass it through absolute alcohol, 

 clove oil, and turpentine in order to cut it into serial sections after a 

 detailed examination in toto, I am not able to state anything definite 

 as to the histological character of these glands ; but each gland is a 

 goblet-shaped cell with a short neck and with a vesicular nucleus 

 near its larger end, which usually encloses a single, small nucleolus 

 (PI. XIX, figs. 1 & 12). These glandular cells are in most places 

 arranged in a single layer around the vaginal canal, but are in other 

 places also arranged in two layers. Wierzejski'^ states that in C 

 Kroyeri the vaginal canal is muscular, but in the species I have 

 observed its wall is simply membranous. In OiicliocotijU also the in- 

 ternal surface of the vaginal canal is covei'ed with cilia, which are, how- 

 ever, finer and shorter than those of Callcotijle (PI. XV, fig. 10). I have 

 besides observed in the former species that in the hinder portion 

 there is often on the inner surface of the vaginal canal a thin layer of 

 granular substance very similar to that observed in the vas deferens. I 

 have therefore been led to suspect whether the irregular polygonal or 

 goblet-shaped cells drawn in fig. 8, PI. XVI, on the ventral side of the 

 vaginal canal and which were at first regarded by me as the prostate 

 glands be not in reality the Araginal glands ; but hitherto I have not 

 been able to find out any ducts. In all the other species I have not 

 observed any glandular cells around the vagina. 



In many specimens collected during the summer season the 

 vagina was found filled with spermatozoa. I have observed this in. 

 Microcotijle, Axine, and Tristomiim ; and since, as I have said in my 



1). Wierzejski— Z. c. p. 558. 



