FURTHER RESEARCHES ON NORTH AMERICAN ACRIDIID^. 17 



At Ashdown, in the lowlands of the southwest corner of the State, 

 the following species were secured in the adult stage : 



Neotettix femoratus. Arphia xanthoptera. 



Tettix arenosus. Chortophaga viridifasciata. 



Paratettix cucullatus. Hippiscus rugosus. 



Tettigidea lateralis. Spharagemon bolli. 



Syrbula admirabilis. Trimerotropis citrina. 



Orphulella picturata. Schistocerca obscura. 



Orphulella pelidna. Melanoplus bispinosus. 



Dichromorpha viridis. Paroxya sp. 



All of these are found east of the Mississippi River except two 

 Orphulella picturata and Melanoplus bispinosiis which are trans- 

 Mississippian in distribution, common on the prairies from central or 

 western Arkansas to Oklahoma. In the lowlands of Arkansas, as has 

 been noted in reference to other regions of low relief in the south- 

 eastern States, typical xerophile and hygrophile locusts occur in 

 many places side by side in consequence of the topographical con- 

 figuration. No particular features of locust distribution or habitat 

 at Ashdown call for special remark, save the exceeding abundance 

 of Tettiginse, the continually moist sandy loam of the locality seeming 

 especially favorable to the development of great numbers of this group 

 of locusts (see frontispiece). 



The fields of a great part of Arkansas are carpeted with the creep- 

 ing, purple-flowered Japanese clover (Lespedeza striata], or, in the more 

 open stretches, are covered in late summer with a dense growth of the 

 fine-leaved sneeze-weed (Helenium tenuifoliuni) and yellow with its 

 brilliant blossoms. While a few species of locusts (Dichromorpha 

 viridis, Chortophaga, Orphulella} are found more or less commonly 

 in this habitat, it is as a whole less productive than grassy nooks 

 and corners, or fields partly bare and partly grown up to taller weeds 

 and bushes, in short, presenting a greater variety of environment. 



The mountains of Arkansas form two groups the Ouachita ranges 

 south of the Arkansas River and the Ozark plateau north of it. The 

 Ouachita Mountains consist chiefly of several irregular but often east- 

 and-west extending ranges, which for the most part still retain their 

 forest covering. The southern slopes, owing to greater insolation, are 

 very hot and dry, the forest is xerophytic in character and quite open 

 (pi. 3, fig. 2). Characteristic of this habitat are Spharagemon bolli, 

 Melanoplus obovatipennis , scudderi, keeleri, robustus, Boopedon auriven- 

 tris, and Paratylotropidia brunneri. The first five of these are common 

 and widely distributed, the latter two are local and scarce. 



