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 sete and two 
at the apex, the longest of which is scarcely as long 
as the last segment of the abdomen. Anterior antenne 
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 setz, 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 
(fie. 23). Length s'gth of an inch (‘9 mm.). 
LT. 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 Laminarie 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 
