390 ENTOMOLOGY 



(c) Communities of savanna and grassland. 



1. Tropical savanna (dry season) affording habitats in groves, thickets, forest 



margins and grasslands. 



2. Tropical steppe; large herds of mammals. 



3. Temperate savanna; habitats in groves, thickets, forest margins and 



grasslands. 



4. Temperate steppe with cold or dry winters and usually large herds of 



mammals. 



5. Arid, broken, bush-covered steppe with small herds of mammals. 



(d) Communities of winter rain (forests with broad thick leaves) e.g., California 



semi-desert. 



(e) Communities of desert and semi-desert. 



1. Grass, cactus, tree semi-desert with grazing mammals (e.g., South Texas 



semi-desert); succulent semi-desert; shrub-covered semi-desert. 



2. Extreme desert without large diurnal mammals. 

 (/) Arctic and Alpine lands. 



1. Tundra. 



2. Alpine meadows. 



3. Ice fields. 



2. Communities of waters and shores. 



(a) Communities of the sea (Marine). 



1. Communities of the open sea (Pelagic). 



(a) Mid-oceanic communities. 

 (&) Oceanic island communities. 



(c) Sargassum communities. 



(d] Coastal oceanic communities. 



2. Communities of the sea bottom (Benthic). 



3. Littoral communities. 



(a) Communities of eroding shores; subdivisions based on exposure, 

 bottom material and latitude. 



(&) Communities of depositing shores; subdivisions as above plus vegeta- 

 tion. 



(c) Special communities: coral; tidepools; kelp. 



3. Communities of the sea shores. Animals feeding in the sea and breeding on the land, 



or vice versa. Classification based on climate. 



4. Communities of the fresh waters. 



(a) Communities of still waters. Subdivisions based on size, depth and vegetation; 



littoral, pelagic, benthic. 

 (6) Communities of turbulent waters. Sbdivisions based on character of water 



movement. 

 (c) Swamps, marshes, etc. 



Ecology finds its distinctive field of study in communities and 

 succession. These important subjects can not, however, be adequately 

 presented from an entomological viewpoint alone. Furthermore, little 

 has been published on the subject as regards insects. The most that 

 can be done here is to illustrate the subject by naming some of the better 

 known insects as being characteristic of a few typical environments, 

 and to add occasional remarks on adaptation in relation to habitat. 



