Till''. MONOTOMIJ) I'.l'.l'Tf.KS. 



(;r.7 



Tlu' |)i-iii('i|);il i);i|H'i' li-c.-ilitii^' of llic raiiiil\' is hy 



j[or)i. "Synopsis of \\\e .Monoioniiche of th(> Ciiilod States," in 



Trans. Aiiior. Eiit. Soc, Vil 1879, 257-2G7. 

 In irenshaw's list the genera are (by mistake?) (!oinl)iiicd willi 

 those of Trogositid^. Eig:hteen species, distributed among five 

 genera, represent the family, as fnr ns known, in the United States. 



KEY TO INDIANA GENKKA OF MONOTOMTD.T:. 



«. Head slightly pi-olouged behind the eyes, theu suddenly narrowed. 



h. Process of abdomen between the hind co.vie broad, feebly rounded in 



front. 



c. Terminal joint of nntonn:e suddenly broader. Joint nine not wider 



than eight. I- Monotoma. 



cc. Last two .ioints of autenniB enlarged, ninth joint not as wide as 



the tenth; punctures of elytra in rows. Hesperob.^snus. 



hi). Process of abdomen between the hind coxitj triangular, acute; ninth 



joint of antennne as wide as the tenth ; elytral punctures in rows. 



EUROPS. 



aa. Head parallel behind the eyes, not at all narrowed; last joint of an- 

 tennte suddenly enlarged, ninth not wider than eighth. 



II. Bactridium. 



I. Monotoma Herbst. 1793. (Gr., "one + cut.") 



In addition to the distinctly larger terminal joint of antenna?, 

 the members of this genus have the head and thorax usually densely 

 punctured and the elytra with rows of punctures, each bearing a 

 short hair. The surface has a tendency to become coated with for- 

 eign matter, which adheres to the minute hairs and renders the 

 sculpture difficult to study. Of the nine species known from the 

 United States five have been taken in the State, while two others 

 perhaps occur. 



KEY TO INDIANA SPECIES OF MONOTOMA. 



a. AntenuiC slender, joints 4 to 9 longer tb.an wide. producta. 



«(/. Antenm^^ stouter, joints 4 to 9 bead-like or submoniliforni. 



ft. Metasternum densely punctured at middle and sides; thorax densely 

 punctured, 

 c. Head with a rather deep oblique impression on each side of vertex. 



1279. PiciPKS. 

 cc. Head regularly convex, vertex not impressed. 



<l. Thorax longer than wide. 12S0. fulvipes. 



(/(/. Thorax nearly square, or even slightly wider than long. 



e. Thorax with four rather deep impressions. quadrifoveoi.ata. 

 ee. Thorax at most with two feeble impressions near base. 



