HAERIS TO HENTZ. 



Milton, May 16, 1825. 



I have devoted some of my leisure to determining the species 

 of my collection, about eight hundred in number. I have been 

 most sure of foot in Coleoptera, having ascertained the names 

 of two hundred species ; and about one hundred and fifty still 

 remai'n unknown to me. I expect to be able to affix the spe- 

 cific names to these with the assistance of Mr. Say, and for 

 this purpose am about making a case to contain the unde- 

 termined species of all orders remaining in my collection. 

 These I shall send by water to Philadelphia for the examina- 

 tion of Mr. Say, after which they will be returned to me by 

 the same conveyance. I am under the necessity of resorting to 

 this method because I have so few duplicates, and so many of 

 the most interesting species are unique. If you are disposed 

 to cooperate with me in this undertaking and will entrust to 

 my care one individual of each species that you have, I will 

 return to you such of them as I have determined, with the 

 names affixed, and will unite the remaining undetermined spe- 

 cies with mine to be restored, if desirable, as soon as they shall 

 have undergone investigation by Mr. Say and myself. I will 

 confide to you that my principal object (after having become 

 acquainted with the specific names and characters of these 

 insects) is to prepare something like a Faunula Insectorum Bos- 

 toniensis. This I would not attempt from any confidence in 

 my own ability of doing justice to the task, but from a convic- 

 tion that such a work might be useful, and would supply the 

 young entomologist with a cheap and concise account of the 

 species which are common to this vicinity, without obliging 

 him to have recourse to many voluminous, expensive and rare 

 works. 



To accomplish this thoroughly, I must request the assistance 

 of such of my friends as have made entomology a pursuit, so 

 far at least as to ascertain what species may have been observed 

 here. 



