22 ENTOMOLOGICAL SOCIETY 



American farmers, and the defoliation of our shade trees by such 

 pests as the cottonwood and imported elm-leaf beetles cannot be 

 valued from a dollars and cents standpoint. A few scarcely known 

 beetles are one day feeding upon a common weed in some out of 

 the way place ; the next year we hear that they have ruined some 

 crop of that locality, and in only a few years' they have spread 

 over a large area and become recognized as a serious pest. Le- 

 Conte and Horn have well stated that the function of the family 

 seems to be to hold the vegetable world in check by destroying its 

 leaves ; the trouble is that, from our standpoint, the beetles seem 

 to have misinterpreted their duty, and to feel that the superfluous 

 portion is that which man has planted. 



Although, owing to their injurious character, more of the im 

 mature stages of the Chrysomelidag have been described than of 

 any other family of beetles, still the larger portion are unknown, 

 and most of the descriptions are incomplete. Furthermore, no 

 systematic study of the larvae and pupae has ever been made of 

 the family as a whole, so that the general larval and pupal type 

 of the family has never been described that they might be dis 

 tinguished from those of other families, or that the different types 

 and species among the seven hundred composing the family (in 

 Boreal America) could be separated. 



The work which I will briefly outline to-night was commenced 

 as a thesis at Cornell University. Through the kindness of Dr. 

 Howard and Mr. Schwarz, I have been allowed to study the large 

 collection of larvae in the National Museum during the past two 

 years. These, with my own few collections and specimens from 

 various parties, have given me quite a representative series. I 

 have felt the need, however, of material from the tropics where 

 this family is best developed, but all attempts to secure it have so 

 far been in vain. The study of larvae is certainly a new thing to 

 most coleopterists. You will pardon me for quoting in this con 

 nection part of a letter from Mr. Martin Jacoby, than whom there 

 is probably no better authority on the Phytophaga, as it brings 

 out this point very strikingly. " I should have been very glad to 

 be able to assist you in your study of the larvae of the Phytophaga," 

 he says, " but there is absolutely nobody here who ever attempted 

 to collect or study the larvae of beetles, and I know of nobody 

 abroad. I have no doubt that there are such people, but I have 

 never heard of them. I myself am quite ignorant of the early 

 stages of the Phytophaga, but the more well-known ones have, 

 of course, been described in different works." 



When it is attempted to describe the larval type of the Ghrysome- 

 lidae we are at once confronted by two obstacles. On the one hand 

 the larvae of nearly allied families have not been sufficiently studied 

 to make a definition of their characters possible, and on the other, 

 types of the different groups of Chrysomelid larvae are so distinct 



