iSqo.] entomological news. 19 



for many years by the worm and damaged types in the British 

 Museum owes, doubtless, its rediscovery by me to my early visit 

 in that backward season to the New Hampshire hills. 



Random Notes on Lepidoplera. 



BY HENRY SKINNER, M. D. 



Determination of Sex of the Cocoons of Cecropia. — One winter 

 some time ago I collected a large number of Platysamia cecropia 

 cocoons and noticed quite a ditference in their superficial appear- 

 ance, and I determined to see, if I could, what it meant. I had 

 suspected from some previous observations that the two kinds 

 represented the different sexes. I divided the cocoons accord- 

 ingly, putting them in separate boxes, and found, subsequently, 

 that the cocoons in one box produced males and the other females. 

 I separated them by the following characters: the male cocoon is 

 much more compact, lighter in color, and not nearly so baggy as 

 the female and much longer in proportion to its width. A typical 

 male cocoon is three and three-quarters inches in length and one 

 and one-eighth in width, while the female cocoon is but three 

 and one-eighth inches in length by two inches in width. The 

 male cocoons are nearly always found high on the stalks (elder) 

 and the females close to the ground hidden by long grass and 

 dead leaves or other matted material where the elder stalk leaves 

 the ground. The difference in the construction of the two co- 

 coons is very striking, the wrinkled, baggy character of the female 

 ones is noticed at once. There may be some exception, but I 

 think by taking the sum of the characters the sexes may be picked 

 out at once without any difficulty, especially in the cocoons found 

 on elder bushes. The above facts are also true of the other spe- 

 cies in the genus Platysamia, but in a lesser degree. I have 

 separated the sexes of ceanothi in the same way. 



A UNIQUE COLLECTING-FIELD. 



The Eastern Penitentiary is situated at 2 2d and Fairmount 

 Avenue, Philadelphia, in the heart of the city, and is surrounded 

 by a stone wall about 42 feet high. The corridors run from a 

 common centre like the spokes of a wheel, thus leaving some 

 ground between them. Most of the cells have a small yard at- 



