NEMERTEANS 



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lateral nerves are included among them and not pressed against the body wall. The 

 rhynchocoel extends to the posterior end of the body. Its wall consists of interlaced 

 fibres. The proboscis is very stout and the number of nerve strands varies between 

 22 (N 160), 24 (N 168), 25 (N 164) and 26 (N 167). The brain is of fair size and con- 

 forms to the description given by Brinkmann (1917). 



N 160 and 164 were female. Small eggs could be seen close beside the lateral nerves 

 (Fig. 59B). In the other specimens I could find no trace of gonads. 



Genus Crassonemertes, Brinkmann 



Crassonemertes robusta, Brinkmann, 1917 (Fig. 60). 



No colour note was made of this specimen (N 170), taken with Nectonemertes kempt 

 in a 2-metre net at lat. 6° 55' N, 15 54' W, 0-800 m. 



Fig. 60. Crassonemertes robusta, Brinkmann. A, dorsal surface, x 3 ; B, transverse section at the anterior end. 



In spirit the body is white (it had been fixed in corrosive sublimate) and completely 

 opaque. It is broad and flattened and has a distinct tail. A sharp end protruded from the 

 tail; this was afterwards found to be the proboscis (Fig. 60A). The length is 15-0 mm., 

 greatest breadth 7-0 mm., thickness 5-0 mm. 



No epithelium is present. The basement layer is deeply stained and appears to have 

 suffered from shrinkage or drying. The muscle layers are reduced, except dorsally 

 (Fig. 60A). There is no oesophagus. The muscular stomach opens into the long pylorus 

 at the brain. The gut branches are wide and very numerous. They fill the body cavity 

 so that no sign of separate diverticula can be seen in the posterior part of the body when 

 cleared with anilin oil. 



The proboscis is very stout and long. It has twenty-one or twenty-two nerves. The 

 wall of the rhynchocoel is composed of interlacing fibres. The brain is small. There does 

 not appear to be a dorsal strand in the lateral nerves. No gonads could be made out. 



