TILE WTIIBLIGIG BEETLES. 



239 



463 (1505). Gyeinus minutus Fab., Syst. Eleut, I, 1801, 276. 

 Elongate-oval. Above blue-black; sides and margins of elytra bronzed; 



beneatb brownisb-yellow, abdomen black, last ventral segment piceous. Me- 

 dian line of tborax and scutellum with a fine carina ; mesosternum with a 

 deep median furrow. Length 4-4.5 mm. 



Woodland pond near Broad Ripple, Marion County ; scarce. 

 May 15. Readily known by the carinate scutellum and bicolored 

 under surface. 



464 (1508).. Gyeinus fraternits Coup., Can. Nat., 2nd Ser., II, 60. 

 Elongate-oval, rather robust. Above bluish-black, polished, not bronzed ; 



under surface uniform dark reddish-brown. Tips of elytra broadly rounded. 

 Length 6 mm. 



Pine, Lake County and Hudson Lake, Laporte County; scarce. 

 May 20-August 20. Known by the more robust form and entire ab- 

 sence of bronzed lustre. 



465 (1513). Gyrinus ventralis Kirby, Faun. Bor. Amer.. IV, 1837, SO. 

 Oval. Above black, very highly polished, iridescent ; 



margins, sides and suture of elytra bronzed ; beneath red- 

 dish-brown, sides and tip of abdomen a little paler. Length 

 0.5-7 mm. (Fig. 122.) 



Northern half of State; common. March 11- 

 September 19. A handsome species, easily known 

 by its larger size and more brilliant iridescent sur- 

 face. 



G. aquiris Lec. ? 6.5 mm. in length, is recorded 

 from the Middle States and Lake Superior. 



466 (1509). Gyrinus ^eneolus Lee, Proc. Phil. Acad. Nat. ScL, 1868, 368. 

 Elongate-oval. Above uniformly black-bronzed, very shining; beneath 



dark reddish-brown, the last two ventral segments paler. Elytral punc- 

 tures in both this and limbatus larger and more distinct than in dichrous. 

 Length 5-5.5 mm. 



Low meadow ponds near Bass Lake, Starke County, and Hunt- 

 ingburg, Dubois County; scarce. April 8-May 9. 



467 (1511). Gyrinus dichrous Lee, Proc. Phil. Acad. Nat. ScL, 186S, 368. 

 Resembles the next but wholly without bronzed lustre. Punctures of 



elytral stride smaller, more crowded. Length 4.5 mm. 



Lake Maxinkuckee ; scarce. August 17. 



468 (1510). Gyrinus limbatus Say. Trans. Amer. Phil. Soc, II, 1823, 109 ; 



ibid. II. 520. 



Short, broad, but little attenuate behind. Above black, shining, dis- 

 tinctly bronzed, especially so on margins and suture of elytra and front 

 margin of thorax; beneath reddish-brown, the middle segments of abdo- 



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