AMERICAN COLEOPTERA. 



155 



thought desirable and advantageous to science to dissect a few speci- 

 mens so that better illustrations could be presented, and its external 

 "• anatomy fully exposed. In the views of the un- 



der side the sutures have been more distinctly 

 drawn than they can be seen in cabinet spe- 

 cimens. These sutures have been rendered thus 

 distinct by macerating the insect in a solution of 

 caustic potassa, a means so well known to Micvo- 

 scopists as to need no further comment. 



The accompanying outline view (n) will serve 

 to give an idea of the general configuration of 

 the insect. An excellent figure, illustrative of 

 the sculpture, and from which the above outline was copied, may be 

 found in Vol. ix, of the Pacific Rail Road Explorations and Surveys. 

 Head broad, wider behind the eyes, with a broad longitudinal im- 

 pression each side, epistoma truncate. 

 El/PS small, round and finely granulate. 



*• Antennse (Ji) eleven-jointed, inserted under the 



margin of the front^ rather above the base of 



mandibles, in a manner similar to Loricera^ 



glabrous, sparsely punctured on the upper sur- 



''• face, the terminal three joints smooth, entirely destitute of 



("^"^ sculpture. 



(^_ Lahrum (c) transverse, faintly trilobed in front. 



^ — J Mandibles (d) short, obtuse, with a few small teeth and a 

 > ^ slight brush of hair on the inner face. 

 Maxillse (e) entirely corneous, inner lobe with a slight emargina- 

 e. tion internally, and ciliate with spinose hairs in front of 

 and behind the emargination. External lobe corneous not 

 bi-articulate. This lobe appears at all times to be articu- 

 lated beneath the inner lobe, so that from a view in front 

 the insect appears to have double maxillae. 



Maxillary palpi short, four-jointed, the first joint very 

 small, the second and third longer and equal, the last joint equal to the 

 two preceding together, and thicker. 



/■ Llfjida ( /') quadrate, filling the emargination of the 



p«i\wiutf' r\ mentum, broader than long, ciliate on its margins, and 

 ^\ (jy^ without paraglossse. Under surflice with a Y-shaped 

 elevated line. 

 Labial palpi short, three-jointed, supports prominent^ first and se- 



