76 C A PRELUDE. 



specimen of this sex. The males are also at once distin- 

 guished by the peculiar form of the hand of the second 

 pair of legs, which is of large size, strongly curved on 

 its fore margin, whilst the posterior, or palm, is exca- 

 vated ; its distal extremity broadly but obliquely trun- 

 cate, whilst its base is armed with an obtuse point, 

 antagonizing with the tip of the finger, followed by a 

 strong bent and recurved tooth. The first pair of legs 

 are small, and the hand oblong-ovate ; this is also the 

 form of the hands of the second pair of legs in the 

 female, but the base of the palm is defined by a conical 

 point near to the base of the joint. 



Our specimens (like those of Kroyer) have also lost the 

 antepenultimate pair of legs, but in the two posterior 

 pairs the joints are slender, naked, and destitute of spines 

 or points, so as to appear quite simple. 



Several specimens of this species, collected by the 

 Rev. J. Gordon in the Frith of Forth, exist in the Bell 

 Collection of Crustacea, recently presented to the Uni- 

 versity Museum of Oxford by Professor Westwood. 

 They were obtained upon a shell brought up on a had- 

 dock line on the 18th September, 1855. 



