AMERICAN LEPIDOPTERA. 205 



Synopsis of the North American III I.IOTM I \ \ I . 



BY JOHN B. SMITH. 



Under the terra Heliothinae are grouped a number of genera and 

 species, distinguished by no exclusive or peculiar character, and yet hav- 

 ing a certain facies which enables the student to determine almost at a 

 glance the species of the group. Nor is it quite correct to say that there 

 are no peculiar characters — for a large proportion of them are very pecu- 

 liar in the armature of the fore-tibia, which is distinct from any thing 

 found elsewhere, but is not a feature of all the genera. 



There may of course be decided structural characters, which the ex- 

 amination usually accorded to Lepidoptera does not and cannot re- 

 veal. Owing to the dense clothing of the insects, and the absolute 

 necessity of destroying a specimen to examine its anatomical structure, 

 no really scientific classification of them has yet been made, and the 

 present synopsis may at a future time, when the species become more 

 common, be entirely superseded, even though the number of our species 

 be not largely increased. 



In consequence of the well marked structural peculiarities of some 

 members of the group, the study, in the beginning, appeared an easy 

 task. This idea was soon dispelled by the discovery of a certain 

 heterogenity in those genera with many species. In the progress 

 of the work, while I hope to prove definitely that certain genera are 

 unnecessary, it will be observed that specific synonyms are comparatively 

 few. 



Before I had advanced very far in my studies it seemed that I would 

 be compelled to choose one of two courses — either multiply genera on 

 small structural differences, or unite all the species in one or two genera 

 with a large number of species in each, creating sections or divisions, 

 and giving them a sub-generic value. Neither of these courses entirely 

 pleased me, and it was not until I had carefully examined all the species 

 and made all the figures, that I finally arranged them and as they stand 

 in the synopsis. It will perhaps be well that I should state exactly what 

 value I have given to the various structural characters. First the eyes : 

 They are all naked in the group, as I understand it (Lej>ipolj/s and 

 Anartn being excluded, though Lygr. cupes has a very strong affinity 

 in superficial appearance to the former), often rounded and globose, 



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