242 
BRITISH ENTOMOSTRACA. 
They are all parasitic upon fishes and other aquatic 
animals; and, when young, undergo a series of meta- 
morphoses like what takes place in the Cyclopidm. 
Family — ARGULIDiE. 
Arguliens, M. Edwards, Hist. Nat. Crust./ iii. 
ArgulidtE, Leach, Diet. Sc. Nat., xiv. 
— Desmarest, Cons. gen. sur les Crust., 329. 
— Baird, Trans. Berw. Nat. Club, ii, 157. 
Argulina, Kroyer, Tidsskrift, i, 202. 
— Burmeister, Beit, zur Naturg. der Rankenfuss. 
Character . — Head in form of a large circular-shaped 
shield. Antennae short, thick, two-jointed; second pair 
of foot-jaws absent, being replaced by a pair of large 
suckers. 
Genus — Argulus . 
Argulus, Muller, Entomostraca. 
— Jurine fils, Lamarck , Latreille, Cuv. Regne Anim., iv. 
— Leach, Desmarest, Burmeister, HerricJc and Dana, M. Edwards, Spc. 
Monoculus, Linnaeus, Eabricius, Cuvier, Manuel, 8fc. 
Ozolus, Latreille, Hist. Nat. Crust., &c. 
Bikoculus, Geoffroy, Latreille , Genera. 
Character . — As there is only one genus yet known, the 
characters given to the family will suffice also for the 
genus. 
j Bibliographical History . — Baker is the first author in 
this country who seems to have taken notice of the 
Argulus. In his ‘ Employment for the Microscope/ .1753, 
he gives a figure of one which he tells us was found 
sticking to a large carp just taken out of the canal in 
Saint James’s Park.” In size it was about Ath of an inch 
long, and nearly as broad. He figures another, consi- 
derably smaller, taken from the banstickle or prickleback ; 
and as it differed from the former slightly in shape as 
