TYPES OF SPECIES OK CESTODA — KUEFFT. / 



female maturity. There are three testes, all of about the same 

 size, situated near the posterior border of each segment, fairly 

 close to each other. Two may be on the right side, and the 

 other on the left or vice versa. One of the former pair is some- 

 times nearly median in position, in which case it lies just behind 

 and above the vitelline gland. The laterally placed vesicles ate 

 seen to lie postero-laterally from the main mass of the ovary 

 and postero-medially from the vesiculas seminales. The testes 

 approach a little nearer to the dorsal surface than do the ovarian 

 lobes. In transverse section they are seen to extend into the 

 middle portion of the medulla. They are rounded or even pyri- 

 form in shape and measure about 0156 by 0-117 mm. Two vasa 

 efferentia pass away from each testis, one connecting with each 

 vesicula seminalis. These seem to come off from the same point 

 and to diverge from one another very soon. 



There are in each segment two very large and conspicuous 

 vesicula? seminales which vary in size and shape according to the 

 amount of spermatozoa contained in them. The usual form is 

 rounded though it may be elongate or pyriform. In a few 

 instances was seen to be bent in such a way as to form an obtuse 

 angle. The size is about 0*144 mm. in diameter. Each lies 

 quite ventrally in the anterior portion of the proglottid, just 

 laterally to the ovary and antero-laterally to the outer testes. 

 The corresponding vas deferens passes off laterally from its outer 

 extremity. It is a more or less twisted tube which usually 

 becomes thrown into a few coils just before entering the powerful 

 cirrus sac. That part of each vas deferens which lies between 

 the vesicula and the longitudinal excretory canals is surrounded 

 by a dense mass of deeply staining cells, doubtless glandular in 

 nature, which were too imperfectly preserved to allow of any 

 detailed study of them. These are much more abundant on the 

 inner region but gradually become smaller and fewer laterally, 

 none being detected on the coiled portion of the vas deferens 

 near the cirrus sac. Sometimes the glands cover the outer (i.e. 

 lateral) wall of the vesicula too. In transverse section of the 

 segment it is seen that the vas deferens in the neighbourhood of 

 the vesicula lies either medianly or ventrally, but that it grad- 

 ually curves dorsally to pass over- the nerve and the excretory 

 vessels, the latter being displaced towards the ventral surface in 

 this region. 



On entering the cirrus sac the vas deferens soon widens to 

 form an inner vesicula with rather thin walls when compared with 

 the remainder of the tube which lies within the sac and which 

 possesses strong circular muscles in its walls. This part of the 



