188 Records of the Indian Museum. [Yol. XIV, 



the parenchyma is of mterest. In addition to the glands opening sub- 

 marginally on the ventral surface there are some eosinophil glands 

 which open here and there in scattered distribution all over the entire 

 surface of the body. 



The dermal musculature is well developed and consists as usual of 

 circular, diagonal and longitudinal layers. Dorso-ventral fibres occur 

 also in the usual manner. 



The mouth is placed slightly in front of the commencement of the 

 posterior third of the body. The pharynx is inserted a short distance in 

 front of the middle of the body ; its length is nearly equal to one-sixth 

 that of the body. The intestines are quite of the Triclad type. The 

 anterior trunk extends to a point far in front of the brain and usually 

 sends out 8 pairs of lateral branches, which are sometimes bifurcated 

 and sometimes multifurcated. The posterior trunks are provided with 

 13^ — 1.5 subdivided branches. So far as I have observed, Minot's glands 

 are altogether absent in the intestinal epithelium. The food of the 

 worm seems to consist of small organisms, either planktonic or littoral. 

 Remains of a crustacean were found in the pharyngeal chamber and 

 intestinal canal. Moreover, the latter was found to be filled with a 

 dense coagulum. 



Of the excretory canals I have been able to obtain no more insight 

 than a few loops at some points in the dorso-lateral parts of the body. 



The exact arrangement of the nervous system could not be ascer- 

 tained, but it seemed to be quite similar to that of PI. gonocephala. Each 

 longitudinal nerve-trunk forms anteriorly a well-developed brain-mass, 

 those of the two sides being connected by a number of strong commis- 

 sures. From each brain-mass arise a few forwardly-directed sensory 

 and numerous lateral nerves. Posteriorly the longitudinal trunks pro- 

 ceed, running nearly parallel to each other, to the tail-end of the body, 

 and are connected together by fine transverse commissures. Lateral 

 nerves are given of? from the main trunks usually at points opposite to 

 the union of the latter •with, transverse commissures. Marginal nerves 

 could not be brought under observation. 



The genital opening lies nearly midway between the mouth and the 

 nind end of body. It leads into the narrow vestibulum, which receives 

 in front the opening of the penis-sheath. Both the vestibulum and the 

 penis-sheath are lined with a single epithelium resting upon a fine base- 

 ment membrane, beneath which are found circular and longitudinal 

 muscular layers. Eosinophil glands are found all round the vestibulum, 

 into which they open. In one individual a compact mass of spermat- 

 ozoa was observed in the penis-sheath, close to the tip of the penis. 



Numerous testes occur, occupying a dorsal position in the body. They 

 are arranged in two lateral zones beginning from the brain region and 

 extending behind nearly to the posterior end of the body. As is well 

 known, each testis is made up of sperm-mother cells and spermatozoa 

 in all stages of development, surrounded by the tunica propria. Usually 

 each testis gives rise, on its lower side, to a fine testicular canal or vas 

 efTerens. This can be made out only by a careful search. The vasa 

 efferentia run down between gut diverticula, frequently uniting with 



