84 BRITISH COPEPODA. 



hinder margins of the segments, except the last, 

 distantly denticulated ; the dorsal border of each 

 thoracic segment is produced below the middle, so as 

 to form a broadly rounded lip ; the abdominal segments 

 are only slightly convex dorsally. Caudal segments 

 (fig. 22) subconical, appressed, longer than the last 

 abdominal segment, with two small lateral setae and two 

 at the apex, the longest of which is scarcely as long 

 as the last segment of the abdomen. Anterior antennae 

 short and stout (figs. 16, 17), 5-jointed, the ensiform 

 appendage in the male very broad. Outer branch of 

 the first pair of feet (fig. 20) about one third as long 

 as the inner. Lower foot-jaw (fig. 19) short. Fifth 

 foot (fig. 21) elongated; basal joint long and broad, 

 its inner segment oblong, subquadrate, and produced 

 nearly as far as the apex of the second joint which 

 is subtruncate, and bears four long setae, one at 

 the apex, and one at the middle of the inner margin ; 

 second joint long and narrow, 6-setose. The integu- 

 ment of the animal is thick and porous, the pores 

 being arranged in widely- separated irregular patches 

 (fig. 23). Length - 2 \th of an inch ('9 mm.). 



L. lamellifera is not a very abundant species; 

 though I have notes of its occurrence in many different 

 localities, the number of examples obtained from each 

 place is usually small. I have found a very few speci- 

 mens on Laminarice and on muddy rocks near Sun- 

 derland, several in dredgings from a depth of twenty 

 fathoms among the Scilly Islands, off Port Dinlleyn, 

 North Wales, Portincross (Ayrshire), and the Islands 

 of Cumbrae and Bute ; from two fathoms in Lough 



