274 
BRITISH ENTOMOSTRACA. 
1. Lepeoptheirus Stromii. Tab. XXXII, figs. 8, 9. 
Caligtjs Stromii, Baird, Trans. Berw. Nat. Club, 1847. 
Laxe luus, Strom , Kiobenhavn. Selsk. Skrift., x, 23, t. 7, f. 1-7. 
Caligus yespa, Edw. Thompson, Ann. and Mag. Nat. Hist., xx, 248. 
Description. — Female. Carapace oval. The frontal 
plates not very prominent. Thorax about the same length 
as carapace ; last articulation narrower at upper extremity, 
broad posteriorly, and terminating in two rounded lobes. 
Abdomen long and narrow, nearly as long as the last joint 
of thorax. Caudal plates of moderate size, and giving off 
several stout, short, plumose setae. Sternal fork short, 
with simple branches. The horny tubercles on the median 
line of posterior portion of thorax large, and simple. 
Oviferous tubes long, three or four times the length of the 
animal. Length of body (exclusive of tubes) about half 
an inch. 
Male. The male is much smaller than the female. The 
carapace is oval, and much longer in proportion to the 
thorax than in the female; thorax oval-shaped, narrow, 
and notched rather than lobed posteriorly; the outer 
angles in form of a small protuberance, and armed with 
two or three short setse. Abdomen much shorter than in 
female ; terminal setae of caudal appendages longer and 
finely plumose. 
This species approaches very nearly the description of 
the Caligus vespa of M. Edwards. The vespa , however, 
is only three lines in length, and has the carapace narrow 
in front, and very broad posteriorly, and is as broad as 
long, while in this species the carapace is almost an exact 
oval, and the animal is half an inch in length. In vespa , 
the horny tubercle at the base of the thorax is small and 
setiferous ; and in this species it is simple, and of consi- 
derable size. 
Hah. — Berwick Bay; taken off the salmon, August 
1844, W. B. Salmon at Berwick, Dr. Johnston. County 
Down, off the Sahno trutta, August; Salmo salar , July; 
