Chap, xxii.] 



PELAGIC NEMERTINE. 



497 



colour. The worm is provided with a proboscis like that of 

 other Nemertines, which may be compared with that shown in 

 the figure of the land Nemertine, but it is not armed with 

 stylets as in the latter animal. Pclagonemertes is devoid of eyes 

 and apparently of any other special sense organs. It con- 

 stitutes a special family of Nemertines, the Pelagonemertidcc* 



PELAGONEMERTES ROLLESTONI. 



The branched digestive tract is shaded dark ; behind its central tube is seen the 

 wide sac of the proboscis. The proboscis is seen at the upper extremity of the 

 body, partly protruded. Beneath it is the mouth, with a folded opening; 

 shaded dark. On either side of the mouth are the nervous gan^ha, giving oft 

 each a long nerve tract which passes to the extremity of the bodi'. Just 

 exterior to the nerve tracts on each side is seen a row of ovaries. 



The smaller figure shows the proboscis sheath and coiled proboscis, as seen from 

 the hinder surface of the animal. 



Most important to the student of deep-sea phenomena are 

 the Foraminifera with calcareous shells, covered with long 



* For a detailed description of Pelagonemertes, see H. Nf Moseley, 

 "On Pelagonemertes Rollestoni." Ann. and Mag. Nat. Hist'., March, 

 1875; Ibid., Dec. 1875. 



32 



