202 
Marsh—Cyclopidce and Calanidce of Wisconsin. 
Family CYCLOPID^. 
Genus CYCLOPS Mueller. 
KEY TO THE WISCONSIN SPECIES OF CYCLOPS. 
Antennae 17-jointed, fifth foot two-jointed, 
Second joint of fifth foot armed with seta and short spine* 
Terminal joint of outer branch'of swimming feet armed 
externally with three spines, 
Furca of moderate length, americanus. 
Furca elongated, brevispinosus. 
Terminal joint of outer branch of swimming feet armed 
externally with two spines, petrous. 
Second joint of fifth foot with two terminal setae, 
Furca short, navus. 
Furca elongated, pulchellus. 
Second joint of fifth foot, with one terminal and one lat¬ 
eral seta, leucharti. 
Second joint of fifth foot, with three setae, signatus. 
Antennae 16-jointed, fifth foot 3-jointed, modestus. 
Antennae 12-jointed, fifth foot 1-jointed, 
Furca variable in length, armed externally with a row of 
small spines, serndatus . 
Furca short, without armature of spines, fluviatilis. 
Antennae 11-jointed, swimming feet three-jointed, phcileratus. 
swimming feet two-jointed, bicolor. 
Antennae 8-jointed, flmbriatus . 
Cyclops americanus sp. nov. 
Plate IY. Figs. 8-10. 
1882. G. ingens Herrick (23) p. 228, pi. V, figs. 1-8. 
1883. • 11 viridis Cragin (24) p. 3, pi. IV, figs. 8-16. 
1884. “ “ Herrick (26) p. 145. 
