76 GAMMARID^. 



to ascertain that circumstance from specimens in which 

 the more prominent features have been lost. The two 

 anterior pairs of limbs bear an affinity to those of the 

 genus Talitrus. The first pair are strong and robust, 

 having the finger sharp and straight, and incapable of 

 being inflexed upon the hand, which is of considerable 

 length, and gradually tapering to its extremity, where 

 it is not broader than the base of the finger : the coxa 

 of this pair of limbs is very thin and transparent, pro- 

 jecting so far anteriorly that (when the head is bent 

 downwards) it covers all but the last joint of the 

 peduncle of the inferior antennae, which is clearly seen 

 through it. The second pair of limbs are much longer 

 than the first; they are exceedingly thin and slender, 

 and exhibit, in a marked degree, the peculiarity of the 

 genus, in having the third joint remarkably long : the 

 wrist also is very long, being much longer than the hand, 

 which is very short, and furnished with a very short 

 finger, so that the organ can but be of little value in 

 grasping or securing any object of prey, a circum- 

 stance which would again suggest to us the habits of a 

 vegetable rather than a carnivorous feeder. The third 

 and fourth pairs of limbs are similar in form, except 

 that the coxa of the fourth pair has a deep emargination 

 for the reception of the anterior lobe of the coxa of the 

 fifth pair. The three posterior pairs are also formed 

 upon a uniform plan, and scarcely differ in length ; the 

 posterior margins of the broad squamiform plates of the 

 second joints are scalloped, a small hair springing from 

 the depression formed by each scallop. The caudal 

 appendages are short, and in general form approximate 

 those of leaping rather than those of swimming amphi- 

 poda. The penultimate pair are shorter than either the 

 preceding or the following ; they al] have their branches 



