72 



CANCERTD.F. 



DECAPODA. 



BHACHYURA 



CANCER1D/E. 



Pirimela denticulata. 



Cancer denticulate, 



I 'irimcla denticulata, 



MONTAGU, Trans. Linn. Soc. IX. p. 87. t. ii. f. 2. 

 LEACH, Malac. Brit. t. iii. EDWARDS, Hist. Crust. 

 I. p. 424. 



THE general form of this pretty Crab will at once strike 



us as differing very greatly from all those which have 



preceded it. The carapace is very little broader than it 



is long ; the anterior margin is so much arched, as to form 



nearly a semicircle, whilst the posterior portion is regularly 



and greatly narrowed. The latero-anterior margin is 



armed with four prominent teeth, which are triangular, 



slightly curved forwards and upwards, and flattened. The 



front is tridentate ; the two external teeth are triangular, 



flattened, curved a little upwards and inwards, and small ; 



I have seen specimens in which they are almost obsolete ; 



the middle tooth is spiniform, and considerably longer than 



the others. The orbit is also furnished with similar teeth, 



of which there are two above, the inner one being the 



larger ; one beneath, and one at the external angle. The 



