SQUILLA DESMARESTII. 355 



elevations neither so numerous nor so distinct. There is 

 scarcely any trace of longitudinal crests, and it is wholly 

 without spines on the anterior portion. The falciform 

 finger of the claws is armed with five sharp teeth ; the 

 penultimate joint has the upper margin of the groove most 

 minutely denticulated. The four exposed thoracic seg- 

 ments are smooth. The abdomen has on each side two 

 low longitudinal crests, and the sixth segment two addi- 

 tional ones near the centre ; the remainder of the surface 

 is smooth. The terminal segment has a median crest, and 

 the margin is furnished with six strong teeth, the inter- 

 spaces being minutely denticulated. The laminar prolonga- 

 tion of the basilary joint of the appendages of the sixth 

 segment projects nearly in the same proportion as in 

 Sq. mantis ; and the lateral caudal scales do not offer any 

 striking peculiarity. 



The length of full-sized specimens is three inches and 

 a quarter. 



This remarkably pretty species was first distinguished by 

 Risso, who gives a description and an indifferent figure of 

 it in his " Crustaces des environs de Nice," and repeats the 

 description in his subsequent work, " LTHistoire Naturelle 

 de 1'Europe meridional e." A beautiful figure is given by 

 Roux in his unfortunately unfinished work on the Crustacea 

 of the Mediterranean. Its first occurrence on our coasts is 

 recorded by my valued friend Mr. Yarrell in the sixth 

 volume of London's Magazine, with a figure, which is, 

 however, very fallacious, from its being taken from a speci- 

 men which had become corrugated in drying. This 

 specimen, with another, was taken by Mr. Couch on the 

 coast of Cornwall, where they were found amongst sea- 

 weed ; and thus another interesting addition is made to 

 those which I have already had to record, to the partial 



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