LETTER OF JUNE 4TH, 1857. 5 



tion of family and genus. I am unable, however, to decide 

 whether it is of sufficient importance to deserve my attention 

 and study. Will you please advise me on this point, or in- 

 form me whether the question has been solved ? 



In examining your " Manual of British Moths and Butter- 

 flies," with which I am very much pleased, I find no direct 

 notice, in your remarks on the family Psycliidce, of a curious 

 fact which attracted my attention a short time since, nor can 

 I find it noticed in any other work in my possession. A friend 

 presented me with a few cocoons of a member of the genus 

 Psyche, which he found during a visit forty or fifty miles from 

 this place. On opening one of them I found, much to my 

 surprise, the female never leaves its chrysalis case, and that 

 its interior was filled with young larvae, some free and others 

 visible through the transparent coats of the ova ; and that 

 these, together with a quantity of yellowish, floss-silk with 

 which the interior was filled, constituted all that remained of 

 the female. Its development can consequently never advance 

 beyond the condition of a chrysalis, which I supposed hereto- 

 fore never occurred. I am now rearing a large colony of the 

 larvae for the purpose of writing the history of the insect, for 

 I believe it to be undescribed, and ascertaining how the fecun- 

 dation of the ova is effected by the male. This is at present 

 a complete mystery to me. I have never before met with 

 any members of this genus, and would beg to inquire if the 

 facts above mentioned are usual in their history, or does the 

 female escape from the chrysalis case and remain within the 

 cocoon ? 



Permit me to add an observation I made two years ago, 

 and if it be of any use in determining a doubtful question, 

 which I have never seen rationally explained, you are at 

 liberty to make any use of it you wish. It is a description 

 of the means by which Attacus Cecropia effects its delivery 

 from its cocoon, and almost merits the designation of Insect 

 -parturition. I have reared great numbers of this insect, 

 which is one of our largest and most beautiful moths, but 

 have never been successful in witnessing the actual escape 



