1100 



FAMILY LTII. CHRYSOMELTDJL 



KEY TO GROUPS OF INDIANA DONA CIA. 



a. Head and thorax evidently pubescent above. Group A. 



a a. Head occasionally, thorax never pubescent. 



1). Elytra truncate or subtruncate at tip. Group B. 



bh. Elytra rounded at tip; sutural margin. of elytra sinuate behind the 

 middle. Group C. 



Group A. 



But two Indiana species belong; to this group. They are widely 

 different in size and general appearance and, except in the pubes- 

 cence of head and thorax, have little in common. 



KEY TO SPECIES OF GROUP A. 



a. Elytra without pubescence ; hind femora slender, without a tooth. 



2022. PUBICOLLIS. 



aa. Elytra evidently pubescent ; hind femora swollen, toothed. 



2023. PUBESCENS. 



2022 (6523). Donacia pubicollis Suffr., Stett. Zeit, 1S72, 21. 

 Elongate, rather robust, convex. Brown, bronzed; antenna?, tibiae and 



tarsi dusky ; femora reddish-yellow. Head, thorax, scutellum and under 

 surface clothed with short gray, but not dense, pubescence. Third joint of 

 antennae nearly twice longer than second. Thorax longer than broad, me- 

 dian line distinct on basal half ; sides with an obtuse tubercle in front of 

 middle ; disk finely and densely punctate. Elytral punctures small, rounded, 

 rather close set in more or less irregular rows ; intervals rugulose ; tips 

 rounded. Mesosternum narrower than coxae. Length 10-12 mm. 



Lake County; rare. May 20. A few specimens taken by Wol- 

 cott along the beach of Lake Michigan, near Pine. Known hereto- 

 fore only from northern Illinois, where it occurs on water-lilies. 



2023 (6538). Donacia pubescens Lee, Trans. Ainer. Ent. Soc, II, 1867, 55. 

 Elongate, slender, subconvex. Pale reddish-brown, everywhere rather 



densely clothed with short, silky, golden hairs. Antennae piceous, rather 

 stout, third joint one-half longer than second. Thorax slightly longer than 

 broad, feebly constricted near middle, broadly channeled on median third; 

 feebly and obtusely tuberculate each side. Elytral punctures coarse, inter- 

 vals nearly flat ; tips subtruncate. Mesosternum narrower than coxae. Length 

 7-9 mm. 



Lake, Kosciusko and Marion counties; rare. June 9-June 16. 

 Known only from Canada, Illinois and Michigan. Occurs on pick- 

 erel weed. 



Group B. 



This group comprises 14 species, among them the most common 

 ones occurring in the State. All agree in having the elytra more 

 or less truncate at apex. The form in a number of them is flattened 



