THE DECAPOD CKUSTACEA. 175 



it occurs. It is a handsome creature, of reddish brown 

 colour mottled with white, with a strong superficial resem- 

 blance to the true lobster, from which it differs in certain 

 very marked respects. As indicated by its common name, it 

 frequents rocky coasts, the neighbourhood of Lundy being 

 an especially favoured spot. It does not occur on the East 

 Coast. 



The point which will first strike the observer in Palinurus 

 is the total absence of the great forceps so characteristic of 

 lobster and crayfish. All the legs tire similar, and terminate 

 in simply pointed claws, though the first pair show in rudi- 

 ment the condition described as sub-chelate for the shrimp 

 (p. 169). Again, the antennules are half as long as the 

 body, but the length is given by the great elongation of 

 the peduncles, the flagella being exceedingly short. The 

 antennae are very long, longer than the body, and are borne 

 on very stout and spinose peduncles ; the scale is entirely 

 absent. The carapace is very densely coated with spines, 

 of which two are very large and project forward over the 

 eyes, but the rostrum is very small. In both sexes the first 

 pair of abdominal appendages is absent, the others are 

 simple in the male and two-branched in the female. These 

 are only a few of the peculiar characters of Palinurus, 

 which separate it so markedly from the Astacidae; the 

 absence of the great chelae is a point of special interest. 

 It lives chiefly upon the little Molluscs which cluster about 

 the rocks, and is one of the few Crustacea capable of 

 making distinct sounds, produced by rubbing movements 

 of a specially spiny part of the stalks of the antennae. 



The Reptant Crustacea with which we have been hitherto 

 concerned have been large forms showing many points of 

 interest, but which at most can only be hoped for very 

 occasionally on the tidal rocks, and are therefore somewhat 

 beyond our proper sphere. On the other hand, the forms 

 to which we have now to turn are abundant everywhere on 

 the rocks, can sometimes be kept for a considerable period 

 in confinement, and are therefore objects of greater interest 

 to us. These forms are the species of Galathea, and the 

 porcelain crabs (Porcellana). We shall consider these two 

 genera together as forming one family, for though sometimes 

 widely separated, they show in many points great structural 



