OXFORD UNIVERSITY SPITSBERGEN EXPEDITION. 



1135 



The vas deferens is narrow, 7-12 m in diameter, and forms 

 numerous close coils in segm. xii., to which it is confined. It 

 pierces and penetrates the penial body. 



The penial body is of moderate size, -12 mm. in diameter, com- 

 pact, of the lumbriciliine type, spherical, with a definite muscular 

 capsule. 



The ovary, in segm. xii., is bulky. Septum 12/13 is bulged back 

 by ova contained in segm. xii. in such a way as to form an 

 incipient ovisac. 



The S23ermathecse have each a relatively small and thin-v^alled 

 ampulla, subspherical in form, 80-120/1 in diameter. The duct 

 is thick-walled with high epithelium, 70-80 /i in diameter, 

 cylindrical, longer than the ampulla and nearly as thick. There 

 are a number of pyriform groups of cells i-ound the ectal end of 

 the duct. The ampulla, probably communicates with the cavity 

 of the oesophagus at full sexual maturity, though such a patent 

 communication was not visible in my specimens ; in one, however, 



Text-figure 6. 



sap. 



v.s. 



Nephridia of JSncliytrceus cry modes. 

 Sep., septum ; v.s., ventral setal bundle. 



the epithelium of the two organs (ampulla and oesophagus) was 

 continuous. The two ampullse may be separated from one another 

 by a part of the oesophagus ; but in. another case they were con- 

 tiguous — indeed, their walls were fused together. In both these 

 cases the cavity of the ampullae contained spermatozoa. 



Copulatory glands are present, though small, in segms. xiii. to 

 xvi. and perhaps xvii. They do not cover the dorsal surface of 

 the cord at all. There is a small rounded papilla over the position 

 of each gland where the eiand-cells come to the surface. 



Enchytr^us sp. 



Spitsbergen ; among moss in marshy (fresh-water) area near 

 Bruce City ; S.viii. 1921. A number of specimens. 



I regret that this worm is rather too immature to justify my 

 giving it a name. I append a few particulars, which may enable 

 it to be identified when next it is met with. 



