I. '21 51 



small but distinct teeth which diminish in size towards the 

 proximal end. There is a more irregular row of teeth on the 

 inner edge of the palm ; those on the dactyl are similar to the 

 row on the outer margin. There are also a few teeth on the 

 upper surface of the dactyl near its tip. The distal ends of 

 the fingers are not furnished with claws. The outer edge of 

 the hand becomes narrow and sharp in its distal half. The 

 upper surface is slightly convex from side to side and from in 

 front backwards and is covered with minute granules. On 

 the edge of the dactyl and on the outer margin of the fixed 

 finger there are a few groups of fine setae. These are also 

 present in considerable numbers on the lower surface of the 

 hand. The carpus is much longer than the palm of the pro- 

 podite. The right cheliped is much smaller in the female. 



The left cheliped is very slightly built compared to the right. 

 It resembles the same appendage in A. laevis, except in the 

 following points : — setae are present in larger numbers on all 

 the joints ; the teeth on the upper surface of the carpus are 

 confined to the distal half of the joint ; there is no rounded 

 tubercle at the proximal end of the palm ; on the inner margin 

 of the palm there is an irregular line of blunt teeth. 



In the first right walking leg, the lower edge of the merus 

 bears a dense fringe of setae ; there are fewer on the upper 

 margin. There is a row of seven or eight teeth on the upper 

 surface of the carpus. On the upper edge of the propodite 

 there is a row of small scales, some of which bear a few hairs. 

 The dactyl is slightly longer than the propodite and is gently 

 curved. There is a row of small groups of hairs along the upper 

 edge, and a similar row on the inner surface near the lower 

 border. There is a third row on the middle of the outer sur- 

 face. The joint ends in a strong claw. 



In the second right walking leg the setae are less numerous 

 on the merus, and there are only two teeth on the upper sur- 

 face of the carpus near the distal end. 



The first left walking leg resembles the right of the same pair, 

 except that there are only two teeth on the carpus. 



The second left walking leg is similar to the second on the 

 right side. 



The fourth pereiopods are of the usual form. The scaly 

 imbricate area is reduced to a single row of blunt teeth. 



The fifth periopods are similar to those of A. laevis. The 

 sexual tube in the male is perhaps a little longer and thinner. 



There are three unpaired uniramous pleopods in the male. 

 In the female there are four ; the first three are biramous and 

 serve for the attachment of the ova, the fourth is uniramous 

 and takes no part in supporting them. 



The uropods are of the usual form. 



Size. — The carapace of the largest specimen taken by the 

 Ilelga measures 7 nrni. 



General Distribution. — The species has a somewhat restricted 

 range, being confined to the coasts of the United Kingdom 



