OXFORD UNIVEESITY SPITSBERGEN EXPEDITION. 1127 



is attached to a small cliverticnliim of the alimentary tube ; this 

 might be expressed by saying that the proximal portion of the 

 stalk is hollow, its cavity communicating with the alimentary 

 lumen. 



In the cesophagus are large numbers of parasitic Oiliata. The 

 oesophageal epithelium is being shed en masse into the lumen of 

 the canal ; in some places also the cilia are being detached and 

 shed. 



The intestine dilates gradually after passing through the 

 genital segments, about segm. xiii. 



Chloragogen cells begin in segm. vi. 



The coelomic corpuscles have a length of 16-24 ft ; in shape they 

 are elongated, fusiform, pear-shaped, or oval. They are not veiy 

 definite structures, and often seem to be disintegrating and of 

 irregular outline. Some, broader than most, are nucleated. 



The dorsal vessel begins in segm. xiv. The blood from its 

 staining reactions (it stains a pinkish-brown with eosin) probably 

 contained haemoglobin. 



Text-fio'ure 2. 



Cerebral ganglion oi L^imhricUlus cegialites. 



The anteseptal portion of the nephridia consists of the funnel 

 only. The postseptal portion is spindle-shaped. The stout duct 

 is the hinder end of the organ bent downwards and inwards, 

 sometimes forwards as well ; sections of the duct are rather 

 characteristic — always oval in outline and showing radial stria- 

 tic ns in the vv'all. 



The cerebral ganglion (text-fig. 2) has a slightly concave 

 anterior border ; the posterior border is slightly indented in the 

 middle line and rounded on each side of the median indentation. 

 The ganglion is about as long as broad, and is broader in front 

 than behind. 



The testes have the usual constitution in the genus. Each 

 consists of a number of elongated lobes (" divided " testes, using 

 "W elclvs term), which extend into segms. x. and xi. ; each lobe is 

 contained in a membranous sac. which in some cases may be fairly 



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