175 



wasps. The ambush bug and the ambush spider (Misumena alca- 

 toria Hentz) are in active competition upon flowers for much the 

 same kind of food. 



Mirid^e 



Adelphocoris rapidus Say. Dusky Leaf-bug. (PI. XLII, figs. 5 

 and 6.) 

 This leaf -bug was taken from the flowers of the rattlesnake- 

 master, Bryngium yuccifolium (Sta. 11, a), Aug. 13 (No. 55). It 

 was taken in a colony of prairie vegetation at Mayview, 111., Sept. 26, 

 1912, by Miss Ruth Glasgow, who found it captured by Phymata 

 fascia ta. It feeds upon a large variety of plants. 



Lygits pratensis Linn. Tarnished Plant-bug. (PI. XLIII, figs. 3 

 and 4. ) 

 This common plant-bug was taken, copulating, from the flowers 

 of the swamp milkweed, Asclcpias incarnata (Sta. I, d), Aug. 9 (No. 

 12). It is a common fruit and garden pest. Consult Forbes ('05, 

 pp. 119, 263) for figures of this species and references to its life his- 

 tory and habits, and Crosby and Fernald ('14) for a very full account 

 of this species. 



CoLEOPTERA 



CARABID/E 



Lcptotrachclus dorsalis Fabr. 



This ground-beetle was taken in the Spartina colony on the 

 prairie north of Charleston (Sta. I, a) Aug. 28 (No. 179). It is 

 supposed to be predaceous. Its life history is not known to the 

 writer. Blatchley (*io, p. 138) records it as from "low herbs in 

 open woods", and Webster ('03b, p. 22) states that the larva of this 

 beetle destroys the larvae of Isosoma grandc Riley in wheat fields. 



Although no special effort was made to secure members of this 

 family of beetles from the prairie, where they must abound, it is sur- 

 prising that some members of the genus Harpalus were not so 

 abundant as to demand attention. More attention to the ground 

 fauna and less to that found on vegetation would doubtless have 

 given other results. Generally in this family the food habits are 

 predaceous, but there are exceptions, and these include kinds which 

 frequent open places. On September 25, 1900, the writer found 

 specimens of Harpalus caliginosus Fabr. feeding on the flowers or 

 seeds of ragweed, Ambrosia, which grew in a neglected field along 

 Holston River near Rogersville, Tenn., and at Rockford, Tenn., on 

 Sept. 25, 1 901, similar observations were made upon Harpalus penn- 

 sylvanicus DeG. Many years ago Webster ('80, p. 164) made simi- 

 lar observations on this species, and also found it eating wheat, timo- 



