LEPEOPTHEIRUS. 277 
Hab . — Taken from the halibut, in Berwick Bay ; 
Dr. Johnston.* 
5. Lepeoptheirus obscurus. Tab. XXXII, fig. 11. 
Carapace large, rounded oval. Frontal plates well- 
developed. Antennae of considerable size, terminal arti- 
culation giving off at the apex eight or ten short setae. 
Thorax very much smaller than carapace. Last articula- 
tion rounded on upper portion, and square at inferior 
part ; laterally giving off, on each side, two sharp lobes, 
one situated immediately above the other, and armed with 
three rather long, plumose setae. 
Abdomen small ; not more than one third the size of 
last ring of thorax, square-shaped ; the centre of lower 
margin a little produced, and forming two very small 
lobes. Caudal plates stout, and giving off four long, 
finely-plumose setae, the outer of which is the shortest. 
Sternal fork well developed, each branch being bifurcated ; 
the inner branch being much smaller than the outer. The 
fourth pair of feet is very long and stout, extending, 
when stretched out, to fully the length of the thorax and 
abdomen together. The first joint is large, and the last 
terminates in three curved spines, the penultimate joint 
giving off one also. 
Hab . — The brill, taken in Belfast Bay, February and 
March 1844 ; W. Thompson, Esq. 
* I am indebted to my much-valued friend Dr. Johnston, for very fine 
specimens of this pretty species, and for many other proofs of kindness 
during the time I have been preparing this monograph. I am glad of the 
opportunity thus afforded me of bearing testimony to his uniform attention 
and unvarying friendship. 
