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subsequently observed in the recent state by the present author, and described 

 in 1865 under the name of Ilyobates prcetexta, both names being however 

 liable to drop. The present Ostracod is easily recognised from the other 

 indigenous Cytheridae, both by the outwards appearance and by the structure 

 of the appendages. 



Occurrence. I have taken this form in several places of our coast, from 

 the Christiania Fjord to the Lofoten islands, and Norman records it also from 

 Finmark (Vads0). It is generally found in depths of from 20 to 50 fathoms, 

 on a muddy bottom, and is easily detected by the particularity, that when 

 coming in contact with the air, et remains floating on the surface, like the 

 case with Cytheridea papillosa. The movements of the animal are rather slow, 

 and during its crawling on the bottom, the anterior antennae are stroke up- 

 wards in a peculiar manner, somewhat like the case with the Cypridce. 



Distribution. British Isles, Iceland, Bay of Biskay. 



Fossil. Norway, British Isles. 



Subfam. 3. Cytherinae. 



Characters of the subfamily. Shell of very firm consistency, calcareous, 

 with the surface more or less roughly sculptured, in some cases provided with 

 variously formed projections or spines. Hinge generally well developed, with 

 distinct closing teeth in front and behind. Both pairs of antennae strong, sub- 

 pediform; the anterior ones with the terminal part 3- or 4-articulate, and armed 

 in front with 2 or 3 clawlike spines intermingled with thin bristles, last joint 

 more or less produced, and in some cases armed with a claw-like spine in 

 addition to the sets. Legs normally developed and of same appearence in the 

 two sexes. 



Remarks. In this subfamily I propose to comprise the more typical 

 Cytheridae grouping themselves more closely around the genus Cythere (sens. 

 strict.). The chief characters distinguishing this subfamily are given in the 

 above short diagnosis. It is by far the most comprehensive of the subfamilies 

 treated of in the present account, both as to the number of genera and as 

 that of the species. 



