298 REVISION OF THE TENEBRIONID.dE OF AMERII A. 



f 



broadly rounded, never parallel. The thorax is smooth, very finch and sparsely punc- 

 tured, the elytra are coarsely and rather densely punctured and resemble those of escJv- 

 scholtzii. This species extends its range from Oregon to the plains east of the Rocky 

 Mountains. I .ength .41 inch. 



c. lata, Leo., New Species, p. 1 13. 



Similar in form to the preceding, but more broadly oval. The thorax and elytra are 

 densely and finely punctured, from the Island of San Clemente, coast of California. 

 Length .40-.4(i inch. 



< . obesa, Lee., Ann. Lye. V., 181. 



Our smallest species, differing from every other in having the eyes entirely divided. 

 I do not find the lasl two joints of the antennae suddenly larger, as recorded by Lacor- 

 daire, although the antenna- are rather shorter and the joints more compact. 1 do not 

 consider the division of the eyes sufficient for generic separation, more especially in a 

 famih already burdened with genera established on slight characters. 



Length .25 inch. 



Sub-Family III.— TENEBRIONID^l. 



This sub-family contains those species in which the hind margins of the third and 

 fourth ventral segments are coriaceous. The last two segments are consequently capable 

 of a greater degree of motion than is seen in the genera of the preceding sub-families- the 

 middle coxa? are usually provided with a distinct trochantin, the cavities being closed ex- 

 ternally by the mesosternal parapleural in some genera the trochantin is not visible, 

 although the cavities are never so thoroughly enclosed by the sterna as in the Tentyriidae, 

 and the presence or absence of this piece, although of so great value in the preceding 

 sub-families, here loses to a great extent its significance, and genera may occur with and 

 without trochantin in the same tribe; the body is here more frequently winged than ap- 

 terous; the anterior coxa' are frequently sub-cylindrical or transverse in this sub-family 

 and never in the preceding; genera with entire mandibles appear for the first time, and 

 the trilobed front is never seen. 



This sub-family corresponds with Cohort II. of Section II. of Lacordaire, with the ad- 

 dition of tril.es and parts of tribes of Cohorl I., as follows: Tribes XVI part, XVII, XX, 

 \\1\ part. XXV, XXVI, XXVII, and comprises a series of genera presenting almost 

 insurmountable obstacles to the formation of higher groups. Owing to the great insta- 

 bility of the characters among these genera, it is extremely difficult to form a synoptic 

 table of tribes not filled with exceptional cases. Lacordaire admits that table given by 

 him will answer only for a small majority of the genera, and where his list is increased by 



