56 GAMMA RIDiE. 



The inferior margin of this appendage is, like the one 

 last described, fringed with a row of equidistant solitary 

 cilia. The fifth, sixth, and seventh pairs of legs are 

 uniform, except that the second joint of the fifth pair 

 is not developed like a scale, which is the case with the 

 second joint of the two other pairs. Their first joints 

 are small, almost rudimentary, and exhibiting but slight 

 traces of their scale-like character. In all other respects 

 the last three pairs of legs resemble in appearance those 

 of the two preceding pairs, with the exception of being 

 affixed in a reversed position, according to the common 

 type of the order. - 



The three pairs of swimming appendages are long and 

 slender. The three pairs of caudal appendages are 

 strong, stiff", and pointed ; the penultimate is shorter 

 than the other two. The last pair has its branch with 

 the apical joint nearly as long as the preceding. The 

 terminal scale is ovate, fringed with three or four short 

 hairs. 



The colour of this species is white, or fiesh-colour, 

 marked with a large blotch of bright crimson on the 

 back and side, and with a few darker spots of the same 

 colour, as represented by the shading in the accompany- 

 ing figure. A single specimen that we obtained from 

 the neighbourhood of the Eddystone Lighthouse was 

 marked all over with red spots. It only appeared to 

 differ from the present species in having the palm of 

 the hand of the second pair of arms slightly crenulated. 



It appears not to be uncommon on our shores : it is a 

 sublittoral species, and exists probably all round Europe, 

 being found beneath stones in pools, near low water at 

 spring-tides. 



It has the capability of rolling itself very perfectly 

 within the defensive armour provided by its largely- 

 developed coxas. 



