606 ON NEW TAPEWORMS PROM THE HYRAX. 



Janicki be right in inferring that Zschokkeella really differs, a 

 point which I have already gone into above (see p. 590). The 

 description of a second species of Zschokkeella* from a Cerco- 

 pithecus does not throw any further light upon this particular 

 matter. If it were not for the fact that Davainea seems in 

 some of its species to possess paruterine organs of the same type, 

 the African worms referred to might well be regarded as all 

 congeneric, in which case, of course, Zschokkeella would have to be 

 the name. 



Janicki appears to me to be rather hard put to it to separate 

 his hiermicapsifer from Zschokkeella. The differences are certainly 

 small. As already stated, he relies upon supposed differences in 

 the paruterine organs of which I am disposed to doubt the 

 existence. He also mentions the thickness of the muscular walls 

 in Zschokkeella as compared with Inermicapsifer, and a few other 

 points which seem to me to be of minor importance and not even 

 collectively as of generic rank. Janicki's comparisons are based 

 chiefly upon his own account of Inermicapsifer hyracis, which was 

 the only species investigated by him in a detailed fashion. I do 

 not think that a further examination of other species referred to 

 by Janicki will necessarily prove the identity of Inermicapsifer and 

 Zschokkeella throughout. I would point out that my own account 

 in the present paper of /. capensis shows some differences between 

 that species and /. hyracis. These differences are mainly the 

 posterior position of the genital pore, the existence of a vesicula 

 seminalis, the complete separation of two groups of testes, and the 

 presence of a rete mirabile along the course of the sperm-duct. 

 Finally, the uterus is much more rudimentary in /. capensis than 

 in /. hyracis. In some of these characters it would appear that 

 /. settii agrees with my species and differs from /. hyracis. A 

 further examination of these species may show that they agree 

 in other characters not referred to by Janicki in his r6sum6 of 

 these forms. 



I would reserve the generic name Inermicapsifer for these forms 

 and refer " Inermicapsifer " hyracis to Zschokkeella. There now 

 remains my genus Thysanotcenia. Of that genus I have described 

 two species which show many differences of structure. Thysano- 

 tcenia ga'mbiana is, as I now think, undoubtedly to be referred to 

 Zschokkeella, with which it agrees in all points, if we may assume 

 that the paruterine bodies are identical in the two. On the other 

 hand, it will be, as I think, advisable to retain the name Thysano- 

 tcenia for the second species of the genus [T. lemtoris), which differs 

 mainly in the following points : — There is no plexus of excretory 

 tubes and the ventral vessel is very large, the dorsal being appa- 

 rently absent in mature segments ; the ventral vessels are connected 

 in each segment by the usual transverse trunks; the receptaculum 

 seminis is quite different from that of the other forms ; the uterus 



* Z. remota, see v. Linstow, Zeitschr. wiss. Zool. Ixxxii. 1905. 



