OXFORD UNIVERSITY SPITSBERGEN EXPEDITION. 1133 



Bot covering the dorsal surface of the cord ; their shape is slightly 

 different from those of the last species ; the lateral expansions are 

 level with the dorsal surface of the cord, so that there is a straight 

 line all along ; in the former species the Avings rise above the 

 level of the cord. 



I was at first extremely inclined to unite these worms with the 

 last species ; and I am still not quite certain that they are speci- 

 fically distinct. The chief difference is that there are no mucous 

 cells in the present specimens ; they were stained in exactly the 

 same way as the former, yet the mucous cells are extremely 

 obvious at the first glance in the former preparations, while they 

 are entirely absent in these. The thicker cuticle also seems to 

 be a distinction, as well as the shape of the cerebral ganglion and, 

 possibly, though doubtfully, the different shape of the copulatory 

 glands. The appearance of the two worms is also very different ; 

 L. cegiccUtes is dark brown (perhaps in part due to the fixative — 

 Bouin), L. necrophagus pale and semi-transparent (fixative not 

 stated) ; L. cnjialites appears much stouter than L. necro'phagus, 

 though actual measurements hardly bear this out. But the two 

 are closel}^ related ; whether the differences can be put down to 

 the different m^anner of life in the two cases seems doubtful, since 

 one can hardly suppose that the occurrence of these specimens 

 in a dead seal was more than accidental. 



Genus Enchytr^us Henle em. Mich. 

 Enohytr^us albidus Henle. 



Bear Island ; Walrias Ba}" (S.E. of island) ; by shaking plants 

 of dry tandra ; 15. vi. 1921. Four specimens, some of them 

 (? all) mature. 



Same locality; among plants on shaly slope; 22. vi. 1921. 

 Two specimens, both mature. 



Same locality; among plants on top of hill (dry tundra); 

 22.vi.1921. Two specimens, both mature. 



Enchytr^us crymodes, sp. n. * 



Spitsbergen ; among mosses on the bank of a fresh-water pond, 

 more or less under water, Bruce City ; end of July and beginning 

 of August 1921. Several specimens. 



Spitsbergen ; moss by salt marsh, probably reached by ex- 

 tremely high tides, near Bruce City; 8,viii.l921. Numerous 

 specimens. 



Mr. Elton adds a note to the above data: — "These" (the 

 second of the two batches) " were observed to be living on live 

 moss leaves, and seemed to occur among these, but not in the 

 decaying parts of the moss. They survived being frozen solid, in 

 an experiment which I did." 



* Kpvfiwdi]s, icy cold, frozen. 



