240 



TERTIARY INSECTS OF NORTH AMERICA. 



present relatively the least interest, but the absence from American deposits 

 of one whole division of that family, the Membracida, is rather surprising 

 in view of their presence (though rarely) in European deposits and their 

 relative abundance in America to-day. 



The following tabular enumeration of the species and genera occurring 

 in the European and American Tertiaries may serve to present in a clearer 

 light the agreements and disparities between them. The American list is 

 drawn from the descriptions in the present work, while the European is from 

 miscellaneous sources, and includes all those genera and species which have 

 been merely indicntnl as occurring in certain deposits, and so it might fairly 

 be considerably reduced. It should not be overlooked, moreover, that it 

 includes all the amber forms : 



Xuntinai'y list of kitoirti /o*.s/V Hotnoptera. 



If we exclude the amber forms and compare the fauna of the rocks 

 only, we shall reach a very different result, as the following table shows: 



Table of fossil Homoptera from rock 



