TYPE PLATYHELMINTHES. 



lf)3 



d active organs are present in several sets succeeding one an- 

 other, without any external indications of a reduplication of 

 parts. In Tricenophorus the multiplication of the sets of re- 

 productive organs is indicated, however, externally by indis- 

 tinct constrictions of the body, an indication of a tendency 



od- 



FIG. 81. A, Caryophyllceus tnutabilis (after STEIN) ; B, Tcenia saginata (after 



LEUCKART) ; C, anterior eud of T. saginata (after LEUCK.ART). 



od = oviduct. vd vas deferens. 



ov = ovary. vi yolk-glands. 



t = testis. vid = yolk-duct. 



t)S = vesicula seuiinalis. 



for the individual to separate into a number of parts, each 

 possessing a certain amount of individuality. This tendency 

 reaches its highest development in such forms as Bothrio- 

 cephalus and Tcenia (Fig. 81, B}, which consist of an anterior 

 portion, the Scolex (Fig. 81, 6 r ), provided with organs of adhe- 

 sion in the form of suckers, accompanied or not by chitiuous 



