resemble greatly the present day Indo-Malaysian fauna. 

 For some unknown reason all representatives of this re- 

 markable fauna have disappeared from North America. 

 Perhaps this is due to the large insectivorous birds that 

 came in about this time or more probably to the gradual 

 cooling of the northern hemisphere that reached its cul- 

 mination in the Glacial Period and brought about ac- 

 companying changes in the flora and fauna. 



Wherever the Fulgoridae may have originated the deri- 

 vation of the more recent fossil and the existing forms 

 seems to be from the south rather than from the north. 

 According to Webster (F. M. Webster, "The Diffusion of 

 Insects in North America," Psyche, x, pp. 47-58, 1903) there 

 are two main highways of migration from the south ; first, 

 from South America via the Antilles and Florida; and 

 second, from Central and South America via Mexico and 

 the Gulf Coast. The genera Poblicia, Calyptoproctus, and 

 Mysidia are especially representative of Central and South 

 America. The fact, however, that our species in these 

 genera are distinct from those found in those regions would 

 indicate that their presence dates from some ancient time, 

 in our Gulf States. 



As Adams has pointed out, the southeastern United 

 States includes a large number of endemic species of 

 plants and animals. It is therefore most likely that this 

 region is the center of origin and distribution for many of 

 our Fulgorids. 



ECOLOGICAL CONSIDERATIONS 



The native vegetation of any region will indicate to an 

 entomologically trained ecologist the kinds of insects he 

 may expect to find there. Every variation in the soil, 

 rainfall, and climate is reflected in the vegetation and this 

 in turn in the insect fauna. 



Most of the Southern States fall in what Merriam has 

 designated as the Upper and Lower Austral Region. The 

 so-called Gulf Strip of the Lower Austral covers over half 

 of Florida and extends around the Gulf Coast almost to 

 Mexico. The southern extremity of Florida falls in the 

 Tropical Region. These states have so many different soil 



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