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 Cyclopidse. 



Family— ARGULID^. 



AjiGULiENS, 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. 

 AnGULiNA, Kroyer, Tidsskrift, i, 202. 



— Burmeister, Beit, zur Naturg. dev Rankeufuss. 



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. 



Aegulus, MiiUer, Entomostraca. 



— Jtiritiefils, Lamarck, Latreille, Cuv. Rcgne Anim., iv. 



— Leach, Desmarest, Burmeister, Herrick ami Dana, M. Edwards, ^-c. 

 MoNOCULTJS, Linnceus, Fabricius, Cuvier, Manuel, Sfc. 



OzoLTJS, Latreille, Hist. Nat. Crust., &c. 

 BiNOCULTJS, Geoffroy, Latreille, Genera. 



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

 characters given to the family will suffice also for the 

 genus. 



Bibliof/raphical History. — Baker is the first author in 

 this country Avho 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 xoth 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 



