16 PEEFACE. 



anxiety, and it is so with regard to the injuries in- 

 flicted by certain insects upon the crops. It is now 

 twenty-two or three years ago since my old friend 

 Mr. Townend Glover, then Entomologist to the 

 Department of Agriculture, sent me specimens of 

 certain Noctuidse to determine, which had been 

 collected as injurious to different crops. Among 

 them were specimens of the cotton-worm, which 

 had been described by Thomas Say under the 

 name Noctita Xylina. At that time there were 

 very few Noctuidae named in any of the Museums 

 in the country ; and of the nearly fifteen hundred 

 species of Noctuidae now mentioned in our books, 

 not fifteen were known by name in any col- 

 lection in the United States. The descriptions 

 in Prench of M. Guenee had not been translated; 

 a few species had been described by Dr. Harris 

 in his Report on the Insects injurious to vegeta- 

 tion made to the Massachusetts Legislature; but 

 in no public or private collection in the United 

 States were there more than a dozen kinds of our 

 Noctuidae properly named. And it was certainly 

 difficult to obtain any information as to what had 

 been done by European writers in the group. At 

 the present time the general knowledge has in- 

 creased, so that from 600 to 800 species from the 

 East are w^ell known to entomologists, and the 

 immature stages of a considerable number have 

 been discovered. To a large extent the publications 

 by the Department of Agriculture and the difi'erent 

 States have assisted in bringing about this improved 

 condition of affairs. The treatise of Dr. Harris, 



