THE CRUSTACEA 



131 



I have not heard of its being recorded from the coast of 

 England, but it is found in all the Channel Islands, although 

 not commonly. There is a question as to whether this 

 English Channel species is Alpheus ruber or a relative, 

 Alpheus megackeles, but if the specific name (ruber) means 

 " red," as it is supposed to, I shall hold to the name I have 



A I! 



Fig. 51. A. Alpkeus ruber ; B. Nika edulis. f Natural size 



given ; other distinctive characters (plates projecting over 

 eyes, etc.) seem to be hazy and variable. 



Nika edulis (Fig. 51) is placed in the same family as the 

 two last, but does not bear much resemblance to either. 

 It is more shrimp-like. It is about the size of an ordinary 

 prawn, of milk-white colour, and not so firm in the shell 

 as the forms just named. 



One of the legs, usually on the left side, has a peculiar 

 structure : it is double, and can so fold in upon itself 

 that the additional portion is not perceptible. The joint 



