272 
BRITISH ENTOMOSTRAGA. 
Abdomen very short and rounded, broader than long. 
Caudal plates terminated by three tolerably long, plu- 
mose setae. Sternal fork with simple, short, obtuse 
branches. Second pair of foot-jaws very long ; the last 
joint being narrow, long, and terminated by two curved 
claws, one longer than the other. Fourth pair of legs 
stout ; the first joint broad and thick, the last ending in 
one long, stout, curved claw, which is serrated on its 
inner edge, and two short ones. Oviferous tubes of 
considerable length. 
Male. In the male the last joint of thorax is consider- 
ably smaller than in the female, and more rounded ; the 
lobes much sharper, and terminated by the same tubercles, 
but of a larger size. Abdomen about two thirds the 
size of the last joint of thorax. Second pair of foot-jaws 
large. 
Hab. — Belfast Bay, W. Thompson, Esq. Taken from 
the cod and brill, February, March, November, and De- 
cember; Merlangus pollachius, March 1840; the brett 
{Rhombus vulgaris ), March, November, December, 1887 ; 
Merlangus vulgaris , Flem., March, December, 1887 ; 
Corregonus pollan, Lough Neagh, November and Decem- 
ber 1887 ; Gadus cegeljinus, December 1887 ; the plaice, 
Belfast, February 1844 ; Mugil chelo, Belfast, April 
1840. 
4. Caligus centrodonti. Tab. XXXII, figs. 6, 7. 
Female. Carapace obovate ; very much narrower in 
front than posteriorly. Frontal plates well developed, 
deeply notched in the centre. Lunules large, and nearly 
round. Basal joint of antennae large. 
Thorax much smaller than carapace ; last joint quadran- 
gular-shaped, narrow superiorly where it articulates with 
penultimate joint, and crescentic at inferior edge ; nearly 
as broad as long ; at each angle interiorly giving off a 
small tubercle, armed with two setae. 
