324 NATURE SKETCHES IN TEMPERATE AMERICA 



of this region are the prairie and the forest formation. In the 

 former it is characterized by bunchgrass, the blow-sand and 

 blowout associations. In the forest formation the common one 

 is the black-jack oak association. These sand areas, notwith- 

 standing their sterility, offer favorable habitats for many species 

 of insects and plants. The animals frequenting them can, in 

 some cases, be separated into biological groups. On these 

 barren areas I have found insects and spiders enjoying a life 

 of busy activity. The predaceous tiger-beetles, robber-flies, 

 bembecid wasps, jumping and tube-constructing spiders, as 

 well as various locusts are seen in considerable ninnbers, the 

 latter flying about or living on the bare sand. It is in the richer 

 vegetation and older formations among the middle and culmi- 

 nating formations, that is, where the water-content is greater 

 in the soil, we find a corresponding fertility in animal and plant 

 life. In the next chapter I have given a more detailed account 

 of the various species of Orthoptera, or locusts and grasshoppers, 

 as related to their habitats. 



The Haiutat of the Orthoptera 



Few of us realize how perfectly adapted the Orthoptera, 

 or grasshoj)pers, are to their hal)itat. Locally, they are often 

 associated, like plants, into groups, and show a predilection 

 for soils possessing various degrees of humidity. This class 

 of ground-loving individuals are characterized as geodytes. 

 Other forms, like the katydids and tree crickets, prefer living 

 on trees, shrubs, or herbaceous plants, and these are character- 

 ized as phytodytes, in contradistinction to the first-named class. 

 The various subdivisions of habitats are defined at the end of 

 this section. I present herewith a photographic reproduction 

 of an August landscape which is rich in Orthopteran life. It 

 is noteworthy from the fact that it shows a variety of "habitat 

 zones," or areas inhal)ited by grasshoppers. It presents a 

 deciduous forest in the background, with a sandy foreground, 

 over which mesophytic plant societies have become established.^ 

 I will presently show the relation of these plant societies to 



' Mesophytes make up the common vegetation in temperate regions where 

 the soil is rich in humus, with a medium amount of moisture present. 



