fi'J8 DR. F, E. BKUUARU UX 



which appears to be the teimiuation of the vagina, and is 

 practically so since the remaining part has dwindled away. 

 It presents, in fact, the appeai'ance of a lai-ge sperniatheca in 

 an Oligochfetous annelid, and is very unlike the usual form of 

 this part of the vagina in tapeworms, though there are forms 

 which show some likeness to it. It never lodges ova. I shall 

 recur to the structm-e of this sac in comparing it with the 

 corresponding region of the vagina in other Cestodes. After 

 this middle region of the vagina the tube suddenly narrows to a 

 fine canal *, which emerges quite abruptly from its distal and 

 dilated end. This latter tube is of some length and ends in 

 quite an unusual fashion. Instead of opening into a dilated sac, 

 the receptaculum seminis, as in so many tapeworms, the tube 

 opens into a wider horseshoe-^shaped tube, of which the two ends 

 become respectively the duct going to the ovary and that ending 

 in the shell-gland. This region is crammed with spermatozoa, 

 and seems to be undoubtedl}' a cleft receptaculum seminis — that 

 is to say, the ultimate sepiration of this I'egion of tlie female 

 efferent apparatus into oviduct and duct communicating with 

 the vitelline gland through the shell-gland, occurs earlier than 

 is usual and concerns the reoeptacuium itself. This inter- 

 pretation is, I think, justified by a comparison of the present 

 species with Oochoristica, marmoste, a description of which I have 

 lately communicated to this Society f. It will be noticed that 

 the vagina of Oochoristica marmosee shows the same regions as 

 that of the species with which I am concerned here, but that the 

 relative development of the regions differs. Thus the middle 

 region covered externally with gland-cells is short but dilates at 

 the distal end, though to a much less extent than in the present 

 species. The proximal section is very long, and the recept- 

 aculum seminis is a more or less cylindrical widish tube not 

 divided longitudinally as in the new worm described in the 

 piesent paper. I have mentioned that in fully mature pro- 

 glottids the middle region is much altered. It occupies more 

 than half the breadth of the proglottid, and the end which 

 appears to end blindly sometimes curves ra.ther backwards. 

 This part is very much more swollen than the more tubular 

 section which ruiis towards the external pore. 



The icterus of this worm is like that of other members of the 

 genera Linstowift and Oochoristica in its broad features ; but 

 there are some differences that require description. The uterus 

 is, on the whole, very like that of 0. marmosa X\ it is in the 

 same way ventral in position, underlying the ovary but ex- 

 tending laterally more towards the dorsal siirface. Here there 

 is certainly a branched condition of the tubes and spaces to be 



* Very rarely (only in one out of a large numlicr txjuniucci) are ova fo\iuJ liere, 

 an;l their presence dilates the tuhe. 

 + P.Z.S. 1911, p. 274. 

 X P.Z. S. 1914, p. 275, text-fig. 5. 



