BY H. A. BAYLIS. 317 



In yoimg mature segments it has a wide lumen, expanding 

 somewhat towards its inner end to form a ckih-ahaped recepta- 

 culum seminis just before reaching the female glands. In 

 older segments almost the whole vagina serves as a recepta- 

 culum, and has a monilifonii appearance owing to the inclusion 

 of a series of spherical masses of spermatozoa. 



The ovar}' is situated with its centre very sliglitly towards 

 the pore side of the middle hue. It has a transverse diameter 

 of 0.3--0.35 mm., is deeply lobulated, and more or less clearly 

 divided into two lateral masses, of which that on the aboral 

 side is the larger. These masses curve posteriorly, embracing 

 the compact yolk-gland, which lies behind the middle portion 

 of the ovary and is transversely elongated, measuring about 

 0.1 X 0.06 mm. The number of testes in each segment varies 

 between nine and twelve. These are arranged in a single 

 row along the posterior border of the segment and between 

 the dorsal longitudinal excretory vessels. In accordance 

 with the position of the female glands, there are usually fewer 

 testes (not more than six) on the pore side of the j^olk-gland. 

 The uterus persists as a transversely elongated sac with irre- 

 gular walls, extending across nearly the whole width of the 

 gravid segment. The ova have thick, finely-granulated, pale 

 brownish outer shells measuring about 0.065 mm. in diameter. 

 The onchosphere is closely surrounded by an inner shell 

 measuring 0.03-0.0375 mm. in diameter. The embryonic 

 hooks are 0.012--0.015 mm. in length. Between the two shells 

 of the egg is a mass of finely-granular, probably albuminous, 

 material, which sometimes gives rise to the appearance of a 

 third shell or membrane, as in Hymenolepis. 



The systematic position of this species is rather difficult to 

 determine. Some of its characters are suggestive of affini- 

 ties with the Anoploceplialidae. The presence of a rostellum, 

 however, even though rudimentary, seems to indicate that it 

 does not belong to that family. The only other family to 

 which it could be referred seems to be the Hymenolepididae. 

 In most of the genera included in this family the rostellum is 

 either armed or absent. In Hymenolepis, however, it is some- 

 times present in a rudimentary and unarmed condition. 

 Further, Hymenolepis and the other genera included in the 

 subfamily Hymenolepidinae have invariably a persistent sac- 

 like uterus. There appears to be no bar to the inclusion of 

 Chitinolepis in this subfamily, though it could not be referred 



