130 NATURAL HISTORY OF OUR SHORES 



but owing to its fossorial habit it is not often seen. Its 

 eyes, as in those of all the burrowing crustaceans, except 

 one (Squilla), are very small. 



Athanas nitiscens is one of a family named the Alphcedce, 

 but still closely allied to the lobster. 



This crustacean is a little model, like a miniature lobster. 

 The full-grown male is about an inch long, the colour a 

 deep bottle-green, with a line of pale green down the back 

 and some white dots on the sides. The claws are delicately 

 formed, symmetrical, and beautiful. Specimens that have 

 lately renewed their shells are of a pale brown. 



It lives in little colonies of three or four to a dozen, under 

 stones on --shelly bottom, where the stone does not rest 

 evenly on the ground but allows a little pool to remain. 

 It is only found at extreme low-tide level. 



In the same family is a crustacean which is rather start- 

 ling by its brilliancy, and its peculiar habit of making a 

 loud clicking noise. This is Alpheus ruber (Fig. 51). It is 

 of lobsterlike form, about two inches long. Its colour is 

 a brilliant scarlet, except for the large claw, which has a 

 dash of purple. It is firm shelled and brilliant, the shell, 

 both in texture and colour, suggestive of ordinary red 

 sealing-wax. 



The large claw has a peculiar structure : the movable 

 finger, instead of rising vertically from the other, pincer- 

 like, spreads out laterally, and, catching in a little nick, is 

 held there while the closing muscles put strain on it ; then 

 it is released with a snap, and striking on a little plate 

 adapted to receive the impact produces a loud " click." 



This sound can be exactly imitated by smartly and forc- 

 ibly striking the palm of one hand with two fingers of the 

 other. The sound can be heard from many yards' distance, 

 even on a windy day on the shore, and, coming from rock 

 crannies, and from under boulders, it is next to impossible 

 to locate its direction, 



