NORTH AMERICAN COLEOPTERA. 339 



for every organ of the iiiandibulate mouth ; it requires no change of 

 function for any organ ; the galea as a " scraping and tearing" organ 

 being maxillary in its character, not labial ; the development re- 

 quired is simply a farther development of the line started in the 

 Hymenoptera, of which Cresson says : " mouth mandibulate, and with 

 a lower lip or tongue,* sheathed by the niaxillce ;" it requires no further 

 segmentation of any structure; it does not require the total loss of 

 any ])art at alt points of the series, nor does it anywhere require any 

 unusual development or change from a sensory to a functional organ ; 

 finally, it does not require any change in relative position of the 

 parts. 



I have not the least doubt that the series presented by me could 

 be rendered much more conclusive ; but I am hampered by a lack 

 of material, only the few species which I collected as I ran across 

 them during the past season being at hand to draw from. 



If my explanations are correct, some changes nmst be made in the 

 nomenclature of the mouth parts in the Hemiptera as well. 



SOiTIE NOTES ON ARtEOSC HIZIIS. 



BY GEO. H. HORN, M.D. 



Since my Revision of the family Tenebrionidai in 1870, very little 

 has been done beyond the description of new genera and species 

 which have been discovered. All the species of the genus now under 

 consideration have been rare in collections with the exception of 

 s^tdcicol/is, which was found by me in considerable number, and dis- 

 tributed liberally, thereby making the genus known in collections. 

 In the meantime other collectors have, from time to time, found 

 small numbers of one or other species, so that at the present time 

 (juite good series of all the species have accumulated in my boxes. 



The species are all quite small, somewhat ant-like in form, but 

 more depressed, and very sluggish in their movements. Their color 

 is some shade of brown, the surface without lustre. The elytra are 

 elongate-oval, the humeri rounded, the curve descending from the 

 peduncle of the body. The surface of the elytra is costate, there 

 being four elevated costse on each side, excluding the sutural, of 

 which the first and third are nearly entire, the others shorter. Be- 

 tween these costifi are two rows of coarse and deep punctures, never 



* The italics are mine. The enveloping " maxillae" are the galea. 



