ON TWO NEW SPECIES OF CESTODES. 
bS 
(or) 
Os 
17. Contributions to the Anatomy and Systematic Arrange- 
ment of the Cestoidea. By Frank E. Bepparp, M.A., 
D.Sc., F.R.S., F.Z.S8., Prosector to the Society. 
[Received February 10, 1914: Read April 7, 1914. ] 
(Text-figures 1-8.) 
XIII. On Two NEw SPECIES BELONGING TO THE GENERA OOCHO- 
2ISTICA AND ZLINSTOWLA, WItH REMARKS UPON THOSE 
GENERA. 
INDEX. 
Page 
IDMPSAOUOE, (HAVE, SDo We scoocoss. ss05ess0ac0ea0snHD0R9 HDG DR AOOSODDOD ACL) 
Oochoristica marmoseé, sp. N. ........ aubueeadade {i ee) 
Remarks upon Genera Oochoristica ail Dinstowte |. MASI! 
The material upon which the following observations are based 
was collected at the Society's Gardens during September and 
October of last year, and suitably preserved for microscopical 
examination. I was only able to make observations upon the 
living worm in the case of Oochoristica marmose. Both worms 
were parasitic in the small intestine of their host. 
§ LinstowIA AMEIV4, sp. n. 
I have examined three examples of a Cestode from the Surinam 
Lizard, Ameiva swrinamensis, which I place—atany rate, for the 
present—in the genus Linstowia; for I shall call attention on a 
subsequent page (p. 281) to the difficulty of distinguishing Lin- 
stowia and Oochoristica as they have been defined up to the 
present time. 
The worm is a small one, measuring up to 25 mm. in length 
with a diameter (where it is broadest) of 15 mm. There is 
no rostellum and the four suckers are unarmed. The scolex 
(when the worm, at any rate, is in a state of contraction) is 
not wider than the body which follows; the latter gradually 
increases in diameter. A neck is present in which no segmen- 
tation occurs; the rudiments of the generative organs appear 
almost coincidently with the commencement of segmentation. 
The only other external character to be noted is the “alternation 
of the genital apertures, which are always anterior in position 
in the segment. In transverse sections the cortical layer is seen 
to be thick, its diameter in both dorsal and ventral layers being 
fully as great as that of the entire medullary layer in the same 
section. This is one of the reasons which lead me to refer the 
present species to the genus Linstowia as commonly defined. 
Such sections also show the disposal of the longitudinal muscle- 
fibres into bundles. As will be seen from text-fig. 4 (p. 270) 
there is only one row of bundles, which is by no means so marked 
as is that in two other species belonging to the same genus or to 
