THE CRUSTACEA 



139 



genera 

 " fixed " 



The Palinuridce. Of this splendid family we have but 

 two representatives on the British shores or in the Channel. 

 They are characterised by a rough spiny armour ; the 

 abdomen is broad, and the tail fins fleshy, only the portions 

 near the hinges being calcified. 



There are no " claws," in the regular way, only the 

 movable finger (Dactylopodite) being developed. The pro- 

 minence on the large part of the limb (the Carpopodite), 

 which in most other 

 forms the 

 part of the 

 pincers, is represented 

 only by a sharp spine, 

 against which the finger 

 closes a rather severe 

 pinching apparatus, none 

 the less. 



The young emerge in a 

 curious form, termed a 

 Phyllosoma. These are 

 transparent, flat, leaflike 

 organisms, about half-an- 



inch across when a few days old. They have long, slender 

 limbs, with branchial appendages. 



Before their life history was known these Phyllosomce 

 were termed " Glass Crabs " (see Fig. 55). 



The best-known example is Palinurus quadricornis, the 

 " craw-fish " of our markets. This is without exception 

 the grandest of the British crustaceans (Fig. 54). 



A full-grown specimen (male) measures about twenty 

 inches from rostrum to tail, and has a girth of eighteen or 

 twenty inches. 



The antennae are stout and long (up to twenty-four inches), 

 ridged, and thickly set with sharp spines. The colour is a 

 marbling or mottling of red and orange. 



Fig. 55. Phyllosoma stage of Craw- 

 fish. Somewhat enlarged 



