LETTER TO THE SECRETARY. 



Office of Unitkd Sta'iks Gkoloiucal and Geographical 



Survey of the Territories, 



Washing tov, Marr/i 1, 1876. 



Sir: Til i)r('s('iitiiiii; to (lie ])iil)lif tlic present iiioiiogrii])h l)y Dr. 

 Packard, 1 teel assured not only of tlie liearty approval of all eiitoinolotrists, 

 but also of scieutifie men generally. 



1 deem it one of the most im[)(Mlant parts of liie work of such surveys, 

 second only to llieir chief oliject, to seizi; upon the op[)orlunity of comijleting 

 such monographs as the present; otherwise, materials which individuals and 

 various expeditions: have been collecling, may remain for years in private or 

 pulilic museums, or perhaps be <lestroyed, without any systematic arrange- 

 ment ever having been made. But this is not the only and greatest benefit to 

 l)e derived from such monographs as the jtresent: it is practically useful as an 

 assistant in the economic entomology of our country, as this memoir emi)races 

 one of the most injurious groups of Lepidopteroiis insects. 



These monographs also enable those who are constructing elementary 

 works, for the use of our colleges and schools to bring into harmony and 

 properly systematiz(> the whole. In tact, so great is the want that is now 

 felt in this respect that I have been called upon to turnish a limited number 

 of copies to some of our Western institutions, to be used directly in instruct- 

 ing the more advanced classes. 



The time has come in this country when monographs, com[)le1e and 

 exhaustive in reference to the tield nnhraced, an* demanded : and no more 

 important work can now lie done in natural history than to bring out such 

 memoirs where the facts and material are sutHcient. 



I thei-(!forc fe«l assured that not only scientists, but the entire educated 

 ))ortion of our people, will give their hearty encouragement in this work. 

 Such publications are monuments which will, in years to come. j)oiiit back 

 to the wisdom of the liberal jiolicy adopted by ("oniiress in aiding the |M-ose- 

 cution oi" this Survey, and allowing it that latitude which enables it thus to 

 work up fully and (wliaustivrly not only the immediate materi.al obtained, 



