152 THE CANADIAN ENTOMOLOGIST. 
9. B. Thuiella? Packard. 
Unknown to me except from the figure in the “ American Naturalist,” 
Vv. 5, p. 427, which does not indicate a dorsal nor an apical spot, though 
Dr. Packard says that it resembles B. pomifoliella. J place it doubtfully 
in this section. 
These, I believe, are the only described American species. 
CORRESPONDENCE. 
MONTRRAL, JULY I4TH, 1873. 
DEAR SIR,— 
I should like to be informed how to distinguish the sexes of moths: 
and butterflies when there is no dissimilarity in the markings of the 
wings, &c. ; also, how to distinguish A. cybele from A. aphrodite, and also- 
to recognize A. atlantis and A. montinus, as in Harris they are not. 
described at all, and Packard only mentions their names. I should also- 
like to know how to preserve spiders and bugs, &c., in the best way. 
Yours, &c., 
He Hak. Montrealte: à 
In the larger moths the sexes may be distinguished frequently by the 
structure of the antennæ, they being more widely pectinate in the male 
than in the female. Where no distinguishing features of this kind present: 
themselves, the relative size of the bodies will enable one to decide this. 
matter, the bodies of the females being usually distended with eggs. A 
more accurate method would be to examine the character of the generative 
organs, for the structure of which we would refer our correspondent to: 
Packard’s Guide, p. 16, 170, 237. 
In answer to the queries relating to cydele, aphrodite and atlantis, we 
quote the following from that excellent work of Mr. W. H. Edwards’: 
“The Butterflies of North America” :— 
‘ Cybele is the larger, and the difference in color between the sexes is: 
much less than in Aphrodite. In the latter the male is much smaller in 
proportion to the female, is brighter colored than Cybele, and has very 
little brown at base of wings. The black markings are noticeably more 
