40 HISTORY OF BRITISH CRUSTACEA. 



Gen. 11. PIBIMELA, Leach. 



Carapace nearly as long as broad. Outer jaw-feet with 

 the third joint having the fourth inserted by its inner edge, 

 and prolonged much beyond it over the epistome. Abdomen 

 of the female of seven joints, of the male formed of five. 



Pirimela denticulata, Mont. sp. Toothed Pii'imela. 

 (Plate III. fig. 1.) — Carapace smooth, strongly bossed on 

 the stomachal, genital, and branchial regions ; concave on 

 the hepatic regions ; latero-anterior margins on each side, 

 with four or five strong flattened teeth. Hands furnished 

 with a slight crest above, and one or two grooved lines on 

 their outer face. 



Not a very abundant species. It is found on the south 

 coast of England; Mr. Norman says it is apparently not 

 uncommon among weeds at extreme low-water mark in 

 Guernsey and Herm. It has been found also on the coasts 

 of Scotland and Ireland. 



Fam. PORTVNIBJE, Leach. 



In these the last pair of feet are much flattened out side- 

 wise, and the toe in particular is dilated into an oval, thin- 

 edged plate, which, striking obliquely upon the water, acts 



