650 MR. F. E. BEDDARB ON 



organs, except in so far as to lemark upon their alternating pores 

 and upon the structure of the ova. Nor does he say anj'thing of 

 the pigmentation of the head, which is so marked a feature of mj'^ 

 species and of the otherwise unrecognisable Tcenia melanocephala 

 of van Beneden *. 



B. mucronata was described from an American Ape, Mycetes 

 niger, and I gather from Mej'ner's description that the Tapeworms 

 themselves were br-oughtfrom Paraguay, and thus real inhabitants 

 of the Monkey in question, which, therefore, had not been 

 infected in a menagerie. This species shows the same pigmenta- 

 tion of the head as mine, and its genei'al shape f is not very 

 different. Nevertheless, it appears to me that in the species 

 described in the present papei' the anterior end is more tapering, 

 and has a very small diameter for a longer stretch. Indeed, the 

 general outline of the worm described in the present paper is 

 more like Meyner's B. conferia +, which is, moreover, a parasite 

 of an Old World Monkey, Macacus radiatus, and therefore, 

 perhaps, more likely on a />r?oH grounds to be identical with mine. 

 I think, however, that B. coiiferta may be put out of covu't in this 

 comparison, for the reason that no mention is made of a black 

 pigmentation in the scolex, which is so clear a feature of my 

 species and of B. mucronatM. Nevertheless, B. covferta agrees 

 with my species and diffei'S from B. mucronata in that the vagina 

 enters the receptaculum suddenly, there being no gradual widening 

 as in B. mucronata, where the tubes are continuous. The suckers 

 are said, however, to be lateral in position, as in B. miicronata§. 

 This is one of the principal reasons which lead me to regard my 

 species as distinct. Of B. muo^onata Meyner writes : — " Sind 

 nicht vollstandig nach vorn, sondern mehr zur Seite gerechtet." 

 In a series of transverse sections through B. cercopitheci, which I 

 have described above, it is very clear that the apertures of the 

 suckers are not lateral noi- slit along the retracted sucker, such as 

 is so obvious in the other species described in the present paper. 



Nor does Meyner describe the remarkable pigment-sheath to 

 each sucker which characterises my species. Furthermore, it 

 appears that B. mucronata has a " neck " ; for Meyner writes ;| : — 

 " Schon etwa 0*9 mm. vom Skolexscheitel entfernt, also in einem 

 Stadium, wo der Korper noch keine Spur einer Gliederung 

 erkennen Ijisst, gruppiren sich," etc. Stiles, in reviewing ^ the 

 characteristics of this species, points out that B. mucronata is 

 also to be defined by the fact that the generative canal passes to 

 the exterior hettveen the nerve-cord on the one hand and the 

 two exci-etorj' vessels on the other. My sections of B. cercopitheci 

 show very plainly that the generative canal passes dorsally to 

 both nerve and lateral excretory vessels. This is particularly 



* Mem. sur les Vers intestinaux, Paris, 1859. 



t Lnc. cit. p]. i. fig. 1. + Loc. cit. pi. ii. fig. 8. 



§ In otlier BertielJa (e. g. in Sluiter's B. plastica, see Centralbl. Bakt. xix. 1896, 

 p. 941) the snckers look upwards. 



II Loc. cit. p. 81. ^ Proc. U.S. Nat. Mus. 1896, p. 145. 



