NORTH AMERICAN ACRIDIID^E. 19 



sylvestris, whose congener celatus of the Virginia mountains bears an 

 even closer resemblance to their northern relative, M. islandicus. 

 On the borders of the clearings and balds and in the more open 

 forests a rank growth of " ol' rich weed " (Eupatorium) is fre- 

 quently found, sometimes covering wide areas. Here Melanoplus 

 amplectens {=blatchleyi) is a characteristic species, and at the head 

 of Roan Valley has extended its habitat into the higher grassy 

 clearings, thriving in myriads among the timothy and velvet-grass 

 {Phleum and Holcus). (See PL 7, Figs, i, 2) Many other thicket- 

 dwelling species were secured at various elevations. 



A COMPARISON OF CAMPESTRAL AND SYLVAN LOCUSTS. 



Campestrian Species. This group as a whole includes locusts 

 of the open country, be it wet or dry, marsh or mountain, strand or 

 crag. Here belong our commonest and best-known locusts or 

 "grasshoppers," of which typical examples are Melanoplus femur- 

 rubrum and Dissosteira Carolina. Considered carefully, we find that 

 all of the Oedipodinae of the Eastern States fall into this group; of 

 the Tryxalinae the following genera : Mermiria, Tryxalis, Syrbula, 

 Orphulella, Eritettix, Stenobothrus , and Mecostethus ; of the Acridiinse 

 Leptysma, Arnilia, Schistocerca , Paroxya, and about fifteen species of 

 Melanoplus (notably angustipennis , atlanis, bivittatus, differentials, 

 extremus, femoratus, minor, propinquus, symmetricus) ; and a number 

 of the Tettiginse. 



Sylvan Species. To this group belong primarily those species 

 which inhabit woodlands and thickets or their borders, such as 

 Chloealtis conspersa, Podisma glacialis variegata, Melanoplus amplectens Y 

 baconi, fasciatus, huroni, islandicus, luridus, morsei, obovatipennis, 

 scudderi, sylvaticus, viridipes, and many of the new species secured 

 during my trip celatus, sylvestris, carnegiei, decoratus, deceptus, devius, 

 divergens, similis, strumosus, and tribulus. To these may properly 

 be added, as already stated, several others whose haunts are amid 

 tangled herbaceous growths wherever found such, for instance, 

 as Dichromorpha viridis, Macneillia obscura, Gymnoscirtetes pusillus, 

 the species of Eotettix and Aptenopedes, and several Tettigince. 



When we compare the component species of these two groups 

 campestral and sylvan we are at once struck with the fact that a 

 very large majority of the former are long- winged, and of the 

 latter are short-winged or apterous, a fact of much biological 

 interest. 



