26 GUSTAF EISEN, ON THE ARCTIC OLIGOCBUETA. 



This species resembles the next with regard to its segmental organs, but both 

 species are easily distinguished through all characters given above. 



3. Neoenchytraeus Stuxbergi n. sp. 



Pl. IX. Fig. 18. 



The supra-cesophagial ganglion is about P/4 times longer than broad. It is broa- 

 dest behind. The swellings of the ventral nerve-chord in all segments are compar- 

 atively large and plain, every second one being larger (fig. 18, e). 



The receptacle consists of a narrow tube furnished at the top with a large cir- 

 cular or oval receptacle for the reception of the spermatozoa. The tube is covered 

 all along with numerous glands (fig. 18, f). 



The vesicle of the efferent duct is sacklike and not twisted. The tube is nor- 

 mally wound, not extending backwards behind the cingulum (fig. 18, g). 



There are no perigastric bodies. 



The segmental organs resemble those of the preceding species, the outer duct 

 being cylindrical and pressed close to the middle lobe, the inner duct, being very small 

 and oval, forming a right angle with the middle lobe (fig. 37). 



The ovaries are in the segments ll th and 12 th . 



The testes are in the 9 th and 10 th segments. 



The spines are of equal length or the inner ones even a little projecting beyond 

 the outer ones in each segment 5. 6. 6. 5. 



The segments are about 56 well defined. 



The length of the body is about 20 m. m. 



The width of the same about 1 m. m. 



The colour whitish opaque. 



Habitat. Novaja Semlia, on several localities, as Besimenaja guba, Gusinnoi cape, 

 Kostin schar and Jugor schar, always under seaweeds on the shore. 



The red-coloured blood of this species places it under Claparede's genus Pachy- 

 drilus. 



The great • similarity between the segmental organs of the two species described 

 above indicates that they are closely allied, but at the same time very distinct trough 

 different shaped cerebral ganglia, receptacles, efferent ducts, and spines. Perigastric 

 cells were not found with certainty in the latter species. 



4. Neoenchytraeus hyaliims n. sp. 



Pl. X. Fig. 20. 



The supra-cesophagial ganglion is nearly twice as long as broad, but its two 

 sides are not so parallel as those of N. Vejdovskyi (fig. 20, f). 



The vesicle of the efferent duct is bent in the middle, the upper part being con- 

 siderably larger than the lower one (fig. 20, in). 



