﻿12 EIGHTH ANNUAL REPORT 



further, not be extracted: it may be coagulated by, or insoluble in - 

 the alcohol, and it is quite essential that we know the nature of the 

 vessel employed. 



In conclusion, the physiological effects of a poison may differ 

 vastly as between cold and warm blooded animals ; the tincture is 

 admitted to have contained an acid (which may be the poisonous 

 principle) and to have killed a frog; and the possible injurious effect 

 of the fumes from burning the insects granted. I theiefore find no 

 reason to change the views expressed a year ago, and it is worthy of 

 note that Prof. A. J, Cook of the Michigan Agricultural College, from 

 experiments somewhat similar to those of Messrs. Grote and Kayser, 

 has arrived at opposite conclusions to those which these gentlemen 

 came to. 



CANKER WORMS. 



(Ord. Lepidoptera ; Fam. Phaljenid^.*) 



In my seventh Report I illustrated and explained the differences in 

 habit and structure between the Spring and Fall Canker worms which 

 had been for so many years confounded. Further investigations dur- 

 ing 1875 have enabled me to still more fully complete the compari- 

 sons there instituted, and have shown that the structural differences 

 are greater than I had at first supposed. These differences led me to 

 separate the insects generically, in a paper read last Fall before the St. 

 Louis Academy of Science. The volume of Transactions in which 

 this paper is published will not be given to the public for many 

 months to come, and in order to lay the subject before the reader in 

 succinct form, and at the risk of repeating much that has appeared in 

 my previous reports, I here reproduce the paper hi extenso, with only 

 such alterations as are necessitated by the proper references to the 

 figures. 



REMARKS ON CANKER-WORMS AND DESCRIPTION^OF A NEW GENUS OF PIIAL^^NIDJE. 

 [Read before tlie St. Louis Academy of Science, Oct. 14, 18V,"i.[ 

 From the time when Wm. Dandridofe Peck published (in 1795) his essay on the 

 Canker-worm, which received a prize from the Massachusetts Socifty for Promoting 

 Agriculture, up to the year 1873, all writers on the subject spoke of the Canker-worm 

 under the impression that there was but one species. Nevertheless two very distinct 

 species have been confounded under this name. The first intimation we have of there 

 being two species is where Harris — after describing at length, as the Canker-worm 

 Moth, not the species first called the Canker-worm by Peck, but the larger species 

 ipometaria) here treated of— uses the following language : " Specimens of a rather 



♦llybernidiu of Uuenee. 



