APSEUDES. 147 



epimera of Milne Edwards, called also the pleura by 

 many authors) existing as articulated appendages, demon- 

 strating two important features in the homologies of 

 these parts : first, that they are really portions of the 

 appendages, being the first joint or coxae of the pleopoda, 

 as first observed by Mr. Spence Bate in his report on the 

 Amphipoda ; and second, that since the peduncle consists 

 of three joints, the second branch in the appendages of 

 the pleon, as in other parts, is shown to take place in- 

 variably at the extremity of the third joint. 



Of this genus we regret that we have obtained but 

 few specimens, too few, indeed, to have enabled us to 

 make complete dissections of the animal. 



As yet we know not the form of the male animal ; 

 it may be similar to that which we figure as the female, 

 but had not Miiller, Rathke, and Lilljeborg described the 

 females of Tanais as resembling the male, we should have 

 suggested that these species were females of Tanais, for 

 it is a singular fact that although of the latter genus we 

 have examined some hundreds of individuals, we have 

 never yet seen one possessing the features of a female.* 



* We are bound, however, in this place to recall attention to Rathke's 

 figure of his Crossurus vittatus with a large incubatory pouch filled with 

 large eggs. 



L 2 



