NEW TAPEWORMS FKOM THE HTRAX. 605 



(2) Hyracotaenia hyracis, sp. n. 



Length about 70 ifrim. ; greatest diameter 4'5 m-m. Body attains 

 its greatest loidth about 6 mm. from anterior end. Testes less 

 numerous. Sperm-duct much dilated posteriorly, sinuous but not 

 coiled anteriorly. Ovary more dorsal, to median side of ivater- 

 vessels ; vitelline glands ventral. Vagina usually mu,ch dilated 

 posteriorly. 



We now come to the consideration of the question of the 

 possible identity of either or both of the above species with any of 

 those enumerated from the Hyrax by Janicki. The only species 

 of that series that can be considered (if, that is to say, there are 

 really no paruterine organs in the forms described by myself) 

 are Tcenia {Anoplocephala ?) gondokorensis of Klaptocz *, Tcenia 

 (Anoplocephala) spatula of v.Linstowf, and Anoplocephala hyracis, 

 YSbV.hepaticaoi ISTassonow J, termed Inermicapsifer spec. ? by Janicki. 

 Of these Klaptocz's species has a small scolex like the species 

 described b}"- me, but also an apical depression (? a rudimentary 

 rostellum) which my species have not. Furthermore, the pro- 

 glottids appear to be much smaller. In the species of v. Linstow 

 we find too great a breadth, and the cirrus sac is too large for 

 comparison with my species. The shape and proportions of 

 Nassonow's species are like mine, but the scolex has a conical 

 process. In all these species the details are insufficient. 



There are thus in African animals — chiefly in Mammals (mostly 

 in the Hyrax (Frocavia), but also in E-odents and Lemurs), but 

 extending to JBirds {Numida ptilorhyncha) — a group of worms 

 which show at least specific difierences, but all of which have the 

 following characters in common, viz., head unarmed and no neck, 

 proglottids wider than long and as a rule very much so, genital 

 pores unilateral, cirrus sac not very large, testes numerous, ovary 

 not double. To these characters may possibly be added, if we 

 exclude the species described above as Hyracotcenia spp., or are 

 led by fui-ther material to interpret their anatomy difierently, the 

 formation of numerous paruterine organs — or egg-capsules as they 

 have been termed by others. 



These characters (excluding the fate of the uterus) seem to me 

 to necessitate the inclusion of this group of worms in the family 

 Anoplocephalidse. 



The various species which agree in the foregoing characters 

 cannot, however, on these alone be massed into one and the same 

 genus without further consideration. If we subtract from the 

 assemblage the species which I have described as Hyracotcenia 

 procavice, and which, as I think, must in any case be withdrawn 

 from the group, the reasons for uniting the rest under a single 

 generic name become more striking. For in this case all of the 

 species possess paruterine organs of the same kind, unless, indeed, 



* S.B. Wien. Ak. 1906. t Jen. Zeitschr. Naturw. xxxv. 1901. 



X Arb. Zool. Lab. Univ. Warschau, 1897. 



