220 



THALASSINAD>E. 



near its origin, with a broad falciform process, the front 

 of which is turned forwards ; the wrist is quadrate, 

 broader than it is long, connected with the arm by a 

 narrow process, and with the hand by its entire breadth ; 

 the hand, exclusive of the fingers, is nearly equilateral, 

 smooth, with a distinct margin at the outer side, the 

 fingers meeting only at the point, the moveable one 

 furnished with stiff hairs : the smaller anterior foot is 

 very slender, the arm becoming somewhat larger at its 

 junction with the wrist, which also enlarges towards 

 the hand, each of these parts being longer than broad ; 

 the hand is small and smooth. The second pair of 

 feet is didactyle, the pincers robust, and the fingers acute ; 

 the third pair has the penultimate joint transversely oval 

 and hairy ; the fourth and fifth pairs nearly filiform and 

 simple. The abdomen is contracted at each extremity, 

 smooth, rounded above, compressed at the sides, the 

 second segment the longest, being as long as it is broad ; 

 the terminal or caudal segment semi-oval. 



The colour of this species is a rather bright red when 

 living, which colour it loses soon after death. 



Length, about two inches. 



The discovery of this remarkable species, which may be 

 considered as the British type of the fossorial form of 

 Crustacea, is due to Montagu who found it on the coast 

 of Devon, where it appears to be not uncommon. It 

 resides, as Leach states, in subterranean passages, similar 

 to those formed by the Gebia. It has been found on the 

 coast of France, and in the Mediterranean. Its claim to 

 be considered as an Irish species is thus stated by Mr. 

 Thompson : " March 25th, 1839. On examining the 

 contents of the stomach of several individuals of the 

 Platessa Pola, wjiich were taken off Newcastle (County 





