218 CLASS CRUSTACEA. 



strong and very arched claw. The last eight are not spiny. 

 The eyes are always apart, and convex. They form their 

 genera in the method of Dr. Leach, but may be united in a 

 single subgenus, under the common denomination of one of 

 them, that of 



Canolira, Leach. (Anilocra, Olencira, ejusd.) 



Oleucira have the lamina? of their fins narrow, and armed 

 with prickles. In anilocra the external lamina of these fins 

 is longer than the internal. The inverse of this is the case 

 with canolira ; besides the eyes are but little granulated, 

 while they are very sensibly so in the preceding. 



In the three following subgenera the second, third, and 

 fourth feet only ai'e terminated by a claw strongly curved, 

 and the last eight are spiny. The eyes are usually but little 

 convex, large, and converge anteriorly. 



jEga, Leach, 



Have the first two articulations of their upper antennas very 

 broad and compressed, while in the two subgenera which suc- 

 ceed, these ailiculations are almost cylindrical. 



Rocinela, Leach, 



Differ from ^^ga, as we have just said, in the form of the 

 first two articulations of their upper antennae, and approach 

 them in their large eyes, which are approximated ante- 

 riorly. 



CONILTRA, Leach, 



Resemble rocinela in their antennae, but the eyes are small, 

 apart, and the edges of the segments are almost straight, and 

 not in the form of scythes, and prominent. 



The last subgenus, among those of this section whose an- 

 tennae are on two lines, whose tail is of six segments, and 



