STUDIES OX THE ECTOPARA.SITIC TREMATODES OP JAP AX. 113 



membrane and consisting of tall, prismatic cells, each with a small 

 nucleus near the base (PL XVIII, fig. 2 ; PL XIX, fig. 7). These 

 nuclei are spherical and vesicular, but stains well, and each contains a 

 single dot-like nucleolus. In Calicotijle the boundaries of the cells are 

 distinct ; but in Monocotijle they become indistinct towards the free 

 surfixce of the cells. The protoplasm of the cell is finely granular and 

 stains a beautiful purplish blue with Kiel nen berg's haematoxylin. 

 In the specimens of Monocotijle examined by me the free borders of the 

 cells remained almost totally unstained and presented a somewhat 

 stringy appearance, as if a layer had been artificially formed by the 

 sticking together of closely aggregated fine cilia (PL XVIII, fig. 2). 

 St.-Remy'^ considers whnt I have regarded as the epithelium of the 

 ootyp as of the nature of a connective tissue and calls it " cuticle " ; 

 and in support of his \iev/ he mentions the fact that although the wall 

 of the ootyp shows a certain tendency towards its external side (/. e. 

 the side tm-ned towards the mesenchyma) to break up into irregular 

 prisms, the lines of separation do not corresipond with the distribution 

 of the niiclei. From his statements elsewhere I gather that the author 

 does not mean by " une, certaine tendance a se dissocier en prismes 

 irreguliers " that he has actually tried to separate these prisms by 

 maceration or other means, but I believe he is here speaking 

 of the lines which I have regarded as cell-boundai'ies. If so, it is to 

 be observed that even in the case of a true epithelium the boundaries 

 do not always seem in cross-sections to coi'respond exactly with the 

 distribution of the nuclei, as actually for example, in the intestine of 

 Monocotijle and Calicotijle. St. -Re my-' admits that " il est vrai- 

 semble que dans le jeune tlge, il y avait la des cellules ;" biit he thinks 

 '• que cette fragmentation ne correspond pas a leurs limites." It is 



1). St.-Ilemy— /. c. pp. 10, 26, 33. 

 2). /. c. p. 26. 



