634 MR. P, E. BEDDAED ON 



to the ovary, but which has also to some extent grown round the 

 sides and lies laterally of the ovary. 



Examining, as an entire object stained and preserved in balsam, 

 some segments at about the same stage of development as 

 those last referred to, it will be noticed that the small and 

 numerous testes occupy in their extension from side to side of 

 each proglottid about half of each proglottid. The lateral areas 

 not invaded by the testes are together about equal in diameter 

 to the middle region where the testes lie. The testes do not 

 reach as far as the lateral excretor}^ vessels, and naturally, there- 

 fore, not to the nerve-cord. 



In the mature proglottides the generative organs have been 

 studied by me chiefly by means of transverse sections. The 

 ovai-ies may be said to be double and lie anteriorly ; the}' occupy 

 a good deal of the available space in the medullary region, and 

 are by no means confined to the middle of the proglottid. The 

 yolk-gland is single and lies behind the ovai'ies. The shell-gland 

 lies medianly in the segment on the opposite side from the ovaries. 

 I could find no reeeptaculum seminis, and the nari^ow vagina runs 

 a straight course for some way before its external opening. 



The testes in the mature segments occupy the posterior region 

 of each proglottid ; but they also extend forward on either side up 

 to the level of the anterior border of the yolk-gland, and even 

 a little beyond, so that in transverse section some ovarian tissue 

 is occasionally seen in the same field with one or more testes. In 

 transverse sections, the male gonads are seen to occupy pretty 

 nearly the whole of the medullary layer of the worm, and are 

 frequently in contact with each other. In segments of individuals 

 which have apparently been stretched during life the testes were 

 in a single row onlj^ dorsoventrally, or, at most, arranged here and 

 there in the form of a " W," one testis being slightly dorsal of 

 another. In such proglottides I never counted more than ten 

 testes in a single row. On the other hand, in proglottides that 

 were rather contracted than extended, the testes were frequently 

 for a considerable extent of the proglottid in two rows, one above 

 the other. In such cases as many as fourteen or even fifteen 

 testes could be seen in one transverse section. The testes are of 

 fair size, and in proglottides which are depressed occupy the 

 whole of the medulla from above downwards. In the other case 

 mentioned above, the medulla accommodated two testes one above 

 the other, and not much room was left unoccupied by these bodies. 

 In fully mature segments the testes are all of approximately the 

 same size, and there must be some fifty or so in a single proglottid. 

 'It is easy to trace a thin membrane surrounding each testis, and 

 completely shutting it off from the parenchymatous tissue of the 

 medulla from neighbouiing testes. This is the state of aflairs 

 that we find in fully mature segments, in which, however, there is 

 as yet no scattering of the eggs in the parenchyma, such as occurs in 

 the terminal segments of the body. In a young specimen mounted 

 entire, the testes were quite plain in certain anterior segments of 



