450 PROCEEDINGS OF THE ACADEMY OF [June, 



morpha viridis, Dissosteira Carolina, Encoptolophus sordidus, Mel- 

 anoplus femoratus, Chortophaga viridifasciata and Orchelimum vulgare. 

 Other common, but somewhat restricted, forms are Stenohothrus 

 curtipennis, Arphia xanthoptera, Arphia sulphurea, Orphulella speciosa, 

 Melanoplus atlanis, Melanoplus minor, Melanoplus scudderi, Xiphi- 

 dium brevipenne, Xiphidium fasciatum, Conocephalus triops, Orcheli- 

 mum spinulosum, Scudderia curvicauda, and Scudderia furcata. 



The following are not uncommon in certain localities, but appar- 

 ently are rare or lacking in many parts of the Piedmont : Hippiscus 

 tuberculatus, Hippiscus rugosus, Xiphidium stricium and Amhly- 

 corypha ohlongifolia. 



The following may in general be regarded as rather scarce members 

 of the Piedmont fauna, although in favorable spots they may be 

 represented in considerable numbers: Eritettix carinatus, Chlceallis 

 conspersa, Spharagemon holli, Melanoplus luridus, Amblycorypha 

 rotundifolia and Atlanticus dorsalis. 



Of exceptional occurrence, though in restricted locations some- 

 times present in surprising numbers, are Pseudopomala brachyptera, 

 Orphulella pelidna, Melanoplus tribulus and Scudderia texensis. 

 The first and third of these have, I believe, been taken only on the 

 Conowingo Barrens of southeastern Pennsylvania. The other two 

 are abundant Coastal Plain forms which only occur in small or 

 moderate numbers in a few Piedmont localities. 



The Orthopteran fauna of the Piedmont is, with some not clearly 

 de'ined exceptions, monotonously uniform throughout. The only 

 subdivisions that I have in any degree been able to recognize are 

 habitat or ecological groups, and even these are not rigidly circum- 

 scribed, the transitions in environmental factors permitting an 

 extensive intermingling of the forms of one habitat with those of the 

 others. 



With these limitations in mind, I think we can recognize tentatively 

 three primary habitats or societies based upon the relative moisture 

 content of the substratum.'" These societies are respectively 



^^ In treating of the various ecological subdivisions, I have in the main adopted 

 the terminology introduced by Morse and Hancock, but have adopted a somewhat 

 different arrangement. Both of these authors primarily subdivide the Orthoptera 

 into ground-frequenting forms (Geophilous society of Morse, Geodytes of Han- 

 cock) and j)lant-frequenting types (Phytophiles of Morse, Phytodytes of Han- 

 cock). This subdivision is to me unsatisfactory because any natural habitat, 

 no matter how dry, will show some vegetation and will accordingly contain both 

 ground-frequenting and plant-frequenting types mingled together in hopeless 

 confusion. To me the best practice seems to be to follow that of the plant ecolo- 

 gists by basing our classification of habitats or habitat-groups primarily upon the 

 available moisture content of the substratum. As all collectors of insects know, 

 the fauna of a marsh is strikingly different from that of a dry barren. 



