40 



exhibiting inside the basal part 3 well defined masticatory lobes; palp slender 

 and somewhat resembling in shape and armature the mandibular palp, though 

 without any setose lamella at the base. Penultimate pair of limbs (maxillipeds) 

 only composed of 2 lamellar segments, the proximal one the larger and pro- 

 vided outside with a well developed vibratory plate, though rather smaller than 

 that on the maxillae, wanting however any trace of masticatory lobes, distal 

 joint narrow oblong in shape and clothed with a few irregularly arranged setae, 

 some of which are densely plumose. Last pair of limbs in female each only 

 represented by a simple rounded lamellae carrying a few setae on the end. 

 This and the preceding pair in male, however, provided with a strongly dev- 

 eloped prehensile appendage, that of the maxillipeds be/ng of a very peculiar 

 appearance, somewhat hatchet-shaped, that of the last pair of limbs more 

 resembling in shape the prehensile palp of the maxillipeds usually met with 

 in male Cypridae. Posterior part of body in both sexes divided by transverse 

 chitinous stripes, as it were, into numerous short segments, some of which carry 

 dorsally long diverging setae. Caudal rami of rather delicate structure, forming 

 2 thin juxtaposed lamellae extending forwards below the body and fringed around 

 the somewhat dilated extremity with a number of peculiar flattened spines, 

 each terminating in a thin setiform lash. Copulatory appendages of male large, 

 symmetrical, forming 2 slender and attenuated pieces curving upwards. Ripe 

 ova received within the shell-cavity for farther development. 



Remarks. This genus was established in the year 1852 by Bosquet to 

 include some fossil Ostracoda found in the tertiary deposits of France and 

 Belgium. The genus was placed by him in the family Cytheridce, near to 

 Cy there. The true systematic relation was first settled in the year 1865 by 

 the present author. 



Several recent species have in the latter years been added to that observed 

 by me, all of them being found in considerable depths of the oceans; but 

 in almost every case the examination of these species has been limited to the 

 shell. The only additional informations about the structural details have, as 

 far as I know, been given by Brady for a species, C. serrulata, taken off the 

 coast of Marocco, and by G. W. Miiller for a Mediterranean species, C. sordida. 

 The genus is represented in the Fauna of Norway by a single species only, 

 to be described below. 



