SOME MAMMALIAN TAPEWOBMS. 637 



of the body is thick. But in Linstowia the testes extend through- 

 ont the proglottid, the genital ducts pass ventrad of the excretory 

 vessels, and there are other differences. Of the Hymenolepida? 

 the following genera only have an unarmed seolex and a single set 

 of generative organs with alternate pores, viz., Catenotcenia, Oocho- 

 ristica, Rhahdometra, Anonchotcenia, Metroliasthes, and Neinato- 

 tcenda. Nematokenia may be set aside as only showing strobi- 

 lisation posteriorly. In Anonchotcenia the testes are anterior 

 and the eggs finally pass into a paruterine organ. In Rhahdometra 

 and Metroliasthes the testes are posterior and at the sides of the 

 ovary, and the genital canals pass between the exci-etory vessels 

 as in the species which forms the subject of the present com- 

 munication ; but in those genera, as in Anonchotcenia , there is a 

 paruterine organ into which the eggs finally pass. There remain, 

 therefore, by this process of exclusion only Catenotcenia and 

 Oochoristica. The former genus must be eliminated, since the 

 genital ducts pass dorsad of both excretory tubes* and the uterus 

 is persistent. The present species is therefore to be referred to a 

 new genus or is to be included in Oochoristica. More recent 

 information about this latter genus than was available to Ransom 

 when he drew up his table shows — what is, indeed, also apparent 

 from that table — that the worm with which I have occupied my- 

 self is an Oochoristica and does not need a new genus for its 

 reception. Ransom's definition is : " Seolex unarmed, without 

 ^ i-ostellum. Single set of i-eproductive organs in each segment. 

 Genital pores irregularly alternate. Testicles numerous, sur- 

 rounding female glands posteriorly and on the sides. Vas 

 deferens coiled ; seminal vesicle absent. Uterus breaks down 

 early and eggs become enclosed singly in egg capsules." I shall 

 now deal with the question of the species to which these worms 

 should be refen-ed. 



So far as I am aware, only two Tapeworms have been described 

 from the gut of Tamandua tetradactyla. The first of these is Taenia 

 tetragonocephcda of Bremser, described by Diesing f, and later, as 

 well as more fully, by Liihe +, whose description disagrees in 

 several particulars with that of Diesing. The most important 

 external disagreement concerns the seolex, which is represented 

 by Diesing as having no neck, while Liihe finds a neck 2 mm. long. 

 This is obviously a matter of some importance ; and I am inclined 

 therefore to regard the Tapeworm described here by myself as 

 not identical with T. tetragonocephala for that reason alone. With 

 the general anatomical description added by Liihe to Diesing's 

 account the worms studied by myself fully agree, and are clearly 

 of the same genus which Janicki § more recently has shown to 

 be Oochoristiccc. Janicki's memoir contains also additional facts 



* This point is not referred to b)- Ransom in his definition of Oochoristica ; 

 I have not accidentally omitted it. 



t Denkschr. k. Akad. Wien, xii. 1856. 



+ Arch. f. Naturg. 1895, p. 199. 



§ Zeitschr. f. wiss. Zool. Ixxxi. 1906, p. 524. See also Zschokke, " Das genus 

 Oochoristica," ib. vol. Ixxxiii. 



Proc. Zool. Soc— 1911, No. XLY. 45 



