J 75 



and this present category of our Sphingid genera includes the 

 most powerful element in our fauna. 



Genera peculiar to North America. 



Names of Genera. A^'o. of Species 



Lepisesia I 



Haemorrhagia 4 



euproserpinus i 



Thyreus I 



Deidamia I 



Arctonotus I 



POGOCOLON . 4 



E VERYX 2 



PAONI AS I 



Calasymbolus 2 



Cressonia I 



Ceratomia I 



DOLBA 1 



Ellema 3 



exedrium i 



25 



I think that the study in this way of the members of any one 

 lepidopterous group will lead to interesting results. But such are 

 only attainable when the material has been closely studied and 

 arranged as I have tried to do with our Sphitigida>.. Since my studies 

 inthesynonymy of the family, the results ofwhich appeared in 1865, 

 I have kept working on the genera and think these, as given in 

 the " New Check List," have acquired a comparatively stable and 

 final condition which will allow of conclusions as to geographical 

 distribution being safely drawn. Especially interesting are such 

 groups as Hceinorrhagia, 'which, is an American development of an 

 Old World type Heviaris, influenced apparently in the extension 

 of the thorax by such South American types as AelLpos. But so 

 long as writers call all or most of our Caudiberbes species of 

 Macroglossa, it is evident that an erroneous idea is given at the 

 outset to our fauna, which does not contain a single form really 

 belonging to that Old World genus. 



While the neuration is not greatly varied in the Sphinges, I find 

 that it is most varied in the Srnerinthi. Good characters are of- 

 fered by which we may, for instance, distinguish Cressonia, in 

 every way a strongly marked and peculiar form. That there is 

 in this group considerable variation in antcnnal structure also is 

 noticeable. We shall find that all the appendages vary in ulti- 

 mate structure, accordingly as a group is plastic or subject to 

 differences. The position of the wing in repose is also unusual 

 in the SvierintJii, the hind wing being pushed upwards ; several 

 of the species look like curled and brown leaves. They are less 

 obvious and more sluggish than the other Sphinges. Our most 

 beautiful species is, I think, Calasymbolus Astyliis. 



Our greatest rarities from the East are Flavofasciata, Cerisii, 



