THE CLICK BEETLES. 745 



KEY TO SPECIES OF CROUP A. 



a. Size larger, 14.5 or more mm. 



1). Sides of tliorax straight or nearly so ; those of elytra distinctly con- 

 verging on apical half. 

 0. Thorax distinctly narrower at apex than base, the sides straight 

 from base to apex ; last ventral of male very coarsely punctate ; 

 length 1.0-16 mm. 1406. cobticinus. 



ec. Thorax very slightly narrower at apex than base, the sides dis- 

 tinctly rounded near apex; length 17.5-18 mm. 



1407. GLANDICOLOK. 



&6. Sides of thorax feebly but distinctly rounded, slightly sinuate in 

 front of hind angles; those of elytra parallel or nearly so; colur 

 darker; length lS-21 mm. 1408. castanipes. 



(HI. Size smaller, not over 12.5 mm. 



d. Disk of thorax evenly and rather coarsely punctate ; carinse of hind 

 angles acute, distinct, close to and parallel to outer edge and reach- 

 ing beyond the middle of thorax. 1409. ignobilis. 

 ihl. Disk of thorax unevenly and sparsely punctate ; cariuse of hind an- 

 gles more or less oblique, not reaching middle, 

 c. Thorax more densely and coarsely punctured on sides than on mid- 

 dle, its sides straight or nearly so from base to apex ; antenna' 

 of male very long. 1410. longicornis. 

 ce. Thorax rather finely and sparsely punctured on both sides and 

 middle, its sides distinctly rounded on apical half. 

 f. A'entral segments of abdomen, except the last, finely and rather 

 sparsely punctate ; reddish or chestnut brown ; length 7-9 mm. 



1411. AMERICANUS. 



ff. Ventral segments with coarse, dense, elongate, more or less con- 

 fluent punctures ; piceous or dark fuscous-brown ; length 10- 

 11 mm. 1412. ciubriventris. 



1406 (4304). Melanotd.s cobticdstus Say, Jouru. Phil. Acad. Nat. Sci., Ill, 



182.3, 174 ; ibid. II, 113, 621. 



Elongate, subconvex. Chestnut or dark reddish-brown, sparsely clothed 

 with long grayish hairs. Second and third joints of antenna; small, rounded, 

 subequal; together much shorter than fourth. Thorax one-fourth longer 

 than wide ; disk with a median Impressed line on basal half ; surface rather 

 sparsely and coarsely punctate, more densely on sides ; hind angles feebly 

 diverging, strongly carinate. Elytral stria? feebly impressed with rather 

 large, close-set punctures ; intervals sparsely and finely punctulate. Length 

 14.5-15.5 mm. 



Knox, Orange, Crawford and Posey counties; scarce. ^Fay 15- 

 June S, Tlie seven specimens at hand are all males. 



1407 (4.''i21). Melanotus gij\.ndicolor Melsh., Proc. Phil. Acad. Nat. Sci., 



II, 1844, 152. 



Elongate, 1lie sides straight and parallel from near the front angles of 

 thorax to beyond the middle of elytra. Chestnut-brown; sparsely pubes- 

 cent with grayish-yellow hairs. Second and third joints of anteuii.-e sub- 



