THE CLICK BEETLES. 



723 



with usually a distinct median impression extending from base to apex, 

 deeper behind ; surface rather coarsely not closely punctate. Elytra widest 

 one-third from base, thence gradually narrowing to apex ; disk striate, striae 

 finely but indistinctly punctured; intervals flat, rather sparsely and finely 

 punctate. Length 5.2-6.5 mm. 



A species of northern range taken in Lake, Laporte and Starke 

 counties. April 16- June 4. Occurs especially beneath rubbish 

 and bark of trees along the dune region bordering Lake Michigan. 



XX. Hypnoidus Steph, 1830. ( Gr., " sleep + form.") 



Small species readily known by the broad prosternum, with the 

 sutures single and convex on the outer side ; the simple tarsal claws 

 and stiff hairs of the tarsal joints. The epimera of the mesothorax 

 do not reach the middle coxae and the latter are therefore closed on 

 the outer side only by the meso- and metasterna. About 20 of the 

 species formerly listed under Cryptohypnus belong here. Of these 

 eight have been taken in the State, while another may occur. 



KEY TO INDIANA SPECIES OF HYPNOIDUS. 



a. Elytra with all the striae entire. 



6. Form depressed, the dorsum quite flat; opaque, densely punctulate 

 and pubescent; color uniform piceous. 1361. steiatulus. 



hi). Form convex. 



c. Thorax coarsely granulate, often in part or wholly finely, longi- 

 tudinally rugose or strigose. 

 d. Apical margin of thorax truncate at middle. 



e. Base of thorax strigose like apex; a distinct, smooth elevated 

 median line ; larger, 3 or more mm. 

 /. Elytra yellow with two sinuous blackish crossbars ; apical 

 third more or less attenuate ; legs wholly pale. 



1362. choris. 



ff. Elytra piceous, each with two yellow spots; apical third 

 scarcely attenuate ; femora fuscous or piceous. 



1363. exiguus. 



ee. Base of thorax smoother than apex ; median line indistinct ; 

 size smaller, not over 2.5 mm. 1364. melsheimeri. 



dd. Apical margin of thorax curved at middle, slightly prolonged 

 over the head. ctjculeatus. 

 cc. Surface of thorax equally punctate, not finely strigose. 



g. Elytra each with two yellow spaces, humeral and subapical ; ely- 

 tral humeri obtuse, striae scarcely more punctate than the in- 

 tervals. 1365. jestivus. 

 gg. Each elytron with a humeral spot only ; humeri rounded, striae 

 more coarsely punctate than the intervals. 1366. perplextts. 

 aa. Elytra with the striae wholly obliterated. 



h. Surface subopaque, distinctly punctate, especially on the thorax : 

 color variable from dull yellow to piceous. 1367. pectoralis. 



