LIFE ON THE OCEAN SURFACE. 



573 



which is branched as in Planarians,* and is of a burnt-sienna 

 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. Pelagonemertes is devoid of eyes 

 and apparently of any other special sense organs. It constitutes 

 a special family of Nemertines, the Pelagonemerticlai.] 



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 ganglia, giving off each a long nerve tract which passes to the extremity of the 

 body. 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. 



* Prof. Giard has lately described a gigantic Nemertine (Avenardia 

 Priei) a yard and a half in length, which has a similarly ramified intestine, 

 otherwise this arrangement does not occur amongst Nemertians. Ann. 

 and Mag. Nat. Hist., Sep., 1878. 



t For a detailed description of Pelagonemertes, »ee H. N. Moseley, 

 " On Pelagonemertes Eollestoni." Ann. and Mag. Nat. Hist., March, 1875 ; 

 Ibid., Dec. 1875. 



