28o 



DISCOVERY REPORTS 



-4 



-4 



i 



PART III. THE PELAGIC NEMERTEANS 



Forty-five pelagic Nemerteans were included in the collection. Of these, thirty-five 

 proved to be Pelagonemertes rollestoni, one of which, taken from a haul of seventeen at 

 St. 107, was sketched in life. Most of the specimens were noted when captured but only 

 one other colour sketch was made. This is reproduced in Plate XVI, fig. 5, and is a new 

 species, Bathynemertes hardyi. 



I have followed Brinkmann (1917) in his classification of the suborder Polystihfera, 



tribe Pelagica. 



Genus Bathynemertes Brinkmann 



Bathynemertes hardyi, n.sp. (Plate XVI, fig. 5; Figs. 56, 57). 



This interesting form, curiously substantial for a pelagic worm, was sketched and 



noted in life by Mr (now Prof.) A. C. Hardy. It was captured at St. 86 (33 25' 00" S, 



6° 31' 00" E) in the \\ m. net at 1000 (-0) m. 



The body was scarlet with black irregular 



markings; the proboscis lighter than the body. 



The body was almost round in section, tapering 



a little to the head and considerably at the tail 



which was not expanded into a fin. 



Form and colour of preserved specimen. The 



body is no mm. long, with a maximum breadth 



and thickness of 25 and 13 mm. It is some- 

 what flattened and is faintly marked by narrow 



annular wrinkles. The tail is more definitely 



flattened. It has, however, neither fins nor lateral 

 lappets. The body has a tendency to curl up at 

 the ends due perhaps to the greater shrinkage of 

 the proboscis and rhynchocoel wall towards the 

 dorsal side of the body cavity (Fig. 56). 



The mouth is not coincident with the rhyn- 

 chodaeum and has a frilled edge. The proboscis 

 is very strong. It is 8 mm. in diameter and 

 covered with papillae. The rhynchocoel extends 

 into the tail. 



The body colour is light brown-orange with irregular patches of dark brown pigment 

 especially on the under side. A lighter streak can be seen down the mid-dorsal and mid- 

 ventral lines, and on each side there is a pale slightly raised lateral line breaking the pig- 

 ment patches. 



Anatomy (Fig. 57 A). The epithelium is almost entirely absent; what there is being 

 ventral (Fig. 57 B). The basement layer is very thick and the circular and longitudinal 

 muscles are fairly developed, little thinner laterally than dorsally or ventrally. Strong 

 strands of muscle pass from the dorsal to the ventral body wall through the body. 



J 



Fig. 56. Bathynemertes hardyi, n.sp. A, ven- 

 tral, B, dorsal aspect of the preserved speci- 

 men, x f approx. 



