878 DR. F. E. BEDDARD ON 
well marked and also occupying, in the form of scattered fibres, most 
of the medullary layer in the region of the paruterine organ. Dorsal 
water-vessel very small, lying dorsal of large ventral vessel, which 
communicates with its fellow posteriorly in each segment by a single 
transverse vessel; no excretory network. Testes surround ovary and 
vitelline gland. Cirrus-sae with a strong muscular wall, and with 
special retractor muscles posteriorly, long and narrow, extending a 
little beyond water-vascular tubes; cirrus without spines ; vas 
deferens with a large and close coil but without vesicula senvinalis. 
Cirrus-sac opens into a cloaca genitalis. Vagina opens behind 
cirrus-sac, terminal region wide and muscular. Uterus at first 
retiform, then irregular in shape with outgrowths, later tubular 
and divided into two chambers by a median septum posteriorly : 
the embryos also separated by ingrowths of walls of uterus. 
Paruterine organ long and styliform, commencing at anterior end 
of proglottid, nearly circular in transverse section when mature, 
appears before uterus. 
Hab. Caccabis melanocephala. 
§ Systematic Position. 
It is clear that a member of the Teenioidea with a totally 
unarmed scolex, with one set of genitalia in each proglottid, and 
with a single paruterine organ, can only belong to one of the 
three genera Rhabdometra, Anonchotenia, or Metroliasthes, or to 
a new genus allied to them. 
As it is, these three genera are very near together ; the generic 
differences as set forth by Ransom mainly concern the position 
of the genital ducts with reference to the water-vessels and the 
form of the uterus. In both of these particulars the present 
species is like Rhabdometra ; sufficiently so also, in other features, 
to warrant its inclusion in that genus. ‘There are, however, 
differences which prevent the reference of my species to any of 
those which have been already described. In none of the 
hitherto described species are the segments so long as in the 
present form. Rhabdometra nigropunctata has the longest of 
any ; but here the most posterior are only 3 x 1. 
There is, to my mind, no doubt that the species which is 
nearest akin to that which I here name Rhabdometra cylindrica 
is Fuhrmann’s recently described Rh. nwmida*, and it will be 
observed that both come from the same part of the world and 
they both infest gallinaceous birds. There are, however, 
sufficient differences to warrant specific separation. Thus, 
Rh. numida is a small species 60-70 mm., and has not, as 
already mentioned, elongated posterior proglottids. Although 
the two species agree in possessing a long cirrus-sac, that 
of Rh. numida is much the longer, reaching as it does to the 
middle of the body. Nothing is said as to the development of 
* Res. Swed. Zool. Exp. Egypt, Pt. ii. 27, p. 36, 1909. 
