500 ANATOMICAL AND rATHOLOGICAL OBSEKVATIONS. 



system, as in the apparently analogous receptacles in Distoma 

 davatmn, nor, as far as I could see, with the vascular system ; 

 hut I have seen it discharge its contents by the posterior 

 orifice, in the manner described by Nordman in Diplostomum 

 ■volvens* 



From the movements of the walls of this receptacle, or 

 from contractions of the animal itself, an active motion of the 

 particles of its contents is occasionally observed. The move- 

 ments occasionally resemble very much those produced by 

 cilia. This sac is apparently a secreting organ, and is pro- 

 bably the only arrangement by which feculent matter is re- 

 moved from the body of the animal. The food of an animal, 

 living as this does in a cyst, is already digested by the walls 

 of its cyst. Its food, therefore, yields no mechanical feculent 

 matter, and its intestinal tube requires no anus. The only 

 outlet which such an animal requires is for chemical feculent 

 matter, which in all animals is the product of secretion, and 

 principally of the lung, gill, or kidney. This sac, may, there- 

 fore, be considered as a respiratory organ or kidney. 



There is another sac, very uniform in shape and size, 

 situated at the posterior part of the body. This sac is 

 elongated, extending from near the outlet of the "cisterna 

 chyli," forward about a fourth of the length of the animal. 

 Its posterior extremity is funnel-shaped, and appears to me, 

 although I have failed in tracing it distinctly, to open 

 externally along with the "cisterna chyli." It appears to 

 possess circular fibres, which constrict it slightly at regular 

 distances. The three anterior fourths of its wall are so thick 

 that the cavity appears linear. This thick part of the wall 

 exhibits an arrangement of fibres or particles perpendicular 

 to its surface. Tlie thick portion terminates by forming a 

 curved projection into the thin posterior part of the organ, 

 the whole arrangement resembling the projection of the 



* Nordman, Micrograph ischc Bcitriige, p. 38, lift. 1. 



