1()S Ml". II. N. Moscley on Pelagonemoites Rollcstoni. 



in picric acid. The inner longitudinal layer consists of stout 

 bands of fibres running parallel to one another. The outer 

 circular fibres are far less developed, and are not gathered 

 into bundles, but cross one another slightly oblifpiely in their 

 transverse course, forming a slight meshwork over the longi- 

 tudinal fibres. 



Beneath the muscular tunic and between its meshes the 

 body mass is filled up with a gelatinous hyaline structureless 

 matter, imbedded in which lie the viscera and the muscles 

 attached about the orifice of the sheath of the proboscis. 

 Internal muscles, except those referred to, were not observed. 



No eyes or other sense-organs were found ; and ciliated sacs 

 were not seen. 



From the circumstance of the only specimen of PeJa<jo- 

 •nemertes having been much lacerated, and from the animal 

 not having been dissected, it will of course require further 

 examination. In the specimen as procured there was a deep 

 constriction of the body at about the junction of the first with 

 the second fourth of its length. This, it appeared pretty 

 evidently, had been caused by the meshes of the net. The 

 posterior extremity was somewhat injured, and its form may 

 not be quite coiTcctly given. Ciliated sacs may be present ; 

 and the structure of the proboscis might throw light on the 

 affinities of the animal. 



The form of the digestive system is the most remarkable 

 feature about PeJagonemertes^ in its close resemblance to that of 

 Dendroccela. In other respects Pelagonemertes is thoroughly 

 Nemertine in structure, being merely modified for pelagic 

 existence. It is remarkable that the gelatinous hyaline mass 

 of the body is not tegumental in character, but apparently 

 liomogeneous with internal structui'es. 



The occurrence of a peculiar bumt-sicnna colour in many 

 very different pelagic animals is remarkable. With many 

 the colouring may be explained as protective resemblance to 

 the oceanic seaweeds. For its occurrence in others, such as 

 Salpa and Pelagonemertes, in an otherwise hyaline body, there 

 may be some common cause, possibly also protective. 



Diagnosis of the Genus Pelagoneviertes, II. N, M. : Body 

 leaf-shaped, gelatinous, hyaline. The anterior extremity of 

 the body hroad and abrupt, the posterior narrowed to a ptoint. 

 The digestive canal with thirteen ptaiis of lateral ramifications, 

 OS in Dendroccela. Integument thin and hyaline, with a thin 

 muscular tunic immediately beneath it, consisting of external 

 circular and internal longitudinal fibres. The animal free^ 

 sw im m ing, ocean ic. 



