242 BRITISH ENTOMOSTRACA. 



Thov arc all parasitic upon fishes and other aquatic 

 animals; and, when young, undergo a series of meta- 

 morphoses like what takes place in the Cyclopidse. 



Family ARGULIDJ3. 



ARGULIENS, M. Edwards, Hist. Nat. Crust., iii. 

 AKGTJLID^:, Leach, Diet. Sc. Nat., xiv. 



Desmarest, Cons. gen. sur les Crust., 329. 



Baird, Trans. Berw. Nat. Club, ii, 157. 

 ARGVLINA, Kroycr, Tidsskrift, i, 202. 



Burmeister, Beit, zur Naturg. der Raukeufuss. 



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, MiUler, Entomostraca. 



,1i' fine Jils, Laninrrk, Latreill?, Cuv. Regne Anim., iv. 



Leach, Desmarest, Burmeister, Ilerrick and Dana, M. Edwards, fyc. 

 MONOCULUS, Linnaim, Fnlif'x-it'x, Ouvier, Manuel, fyc. 

 OZOLUS, iMtreille, Hist. Nat. Crust., &c. 

 BINOCULUS, Geoffrey, Latrcille, Genera. 



Character. As there is only one genus yet known, the 

 characters given to the family will suffice also for the 

 genus. 



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 .'.tliof an inch 

 long, and nearly as broad. I le figmes another, consi- 

 derably smaller, taken from the banstickle or prickleback ; 

 and as it differed from the former slightly in shape as 



