208 FAMIT>Y IV. ^DY'PISOID.^. 



lilt. I,:ist Jiiiiil (.1 iiin \ill;i I'v |i:il|iiis Inincnic: proslcnm I [ifnrfss vpr\ bn-Hil 

 heliind flic cox.-r; liiiKl liliiu' broader; length 4 5 mm. 



II. Hydrocanthus. 



J. Cantiivdkus Sliar]). 1882. (Gr., "l)eetkM water. ") 



Small and sl)ort, .stronyly convex s})e('ies, usually variegated in 

 color above; antennae very short and slender; pectoral plate coarsely 

 sculptured at middle ; hind legs slender, the femora and tibi^ but 

 little flattened, the former contiguous at base. Two species occur 

 in the State. 



;'.!»;{ (1237). Canthydrus bicolok Say. Trans. Amer. I'liil. Soc. IV, 1834, 

 447; ibid. II, 561. 

 Ovate, convex. Head, tliorax and under parts reddisli-yellow ; elj-tra 

 dark reddisli-browu, thickly and rather coarsely punctate. Length 2.5 mm. 



A small but handsome species, taken in Indiana only from Bass 

 Lake, Starke County, and Hudson Lake, Laporte County. Prob- 

 ably occurs throughout the lake region of the State. May 30-Au- 

 gust 20. 



394 (1238). Canthydrus gibbulus Aube. Spec. (>en.. VI, 1S3S. 414. 



Ovate, convex. Head and thorax yellov\', the latter clouded with dusky 

 on the front margin ; elytra dark brown or piceous, with an irregular oblique 

 yellowish cross-bar near the middle. Elytra more sparingly punctate than 

 in hicolor, the dorsal rows of punctures more distinct. Length 2.5 mm. 



Beneath rubbish on beach of Lake Michigan, near Pine, Lake 

 County; scarce. August 1. 



TI. Hydrocanthtts Say. 1823. (Gr.. " water ' beetle. ") 



In addition to the characters given in ttie k'cy, this genus may Iv 

 known by having the last joint of the labial |)alpus very large, tri- 

 angidar and eo ni pressed ; the fi'ont libia' with a strong spur; the 

 hind femora short and stout, tlicii- apical margins strongly ciliated; 

 tibia^ short, smooth, claws e(|ual. But one species is known from the 

 Tnited States. 



3!)5 (1240). IIyduocantiius iricolou Say, Trans, .\iiicr. Phil. Soc. IT. 1823. 

 105; ibid. II, 517. 

 Ovate, convex, attenuate behind. Head. (Jiorax and under ])arts red- 

 dish-.vellow ; elyti-a dark reddish-brown, polished, iridescent. Three irregu- 

 lar dorsal rows (if line punctures visible. I^ength 4—5 mm. 



Throughoni the State; frequent. March 16-August 15. Prob- 

 ably hibernates, as one was taken fi-om mud at the bottom of a pond 

 on the earlier date. 



