16 
The pupae vary in color not only according to age, but after they 
have fully completed their pupal growth; almost every color from a 
dull yellowish green to an ash gray may be encountered. A light 
gray, with numerous black points appears to be the most common; 
those which are parasitized are paler than those that are living. The 
length varies from about .70 to .80 of an inch; a perfect one now be¬ 
fore me measures exactly .75 inch, the precise measurement given by 
Dr. Fitch as the usual length. The angles in the throacic region are 
sharp and somewhat laminated; the two anterior lateral ones present¬ 
ing a single prominence, the posterior ones two prominences; the an¬ 
terior end is armed with a short spine which projects forward. 
The length of time that the summer brood remains in the pupa 
state varies considerably. Dr. Fitch gives the length of time six 
specimens of the summer brood remained in this state, partly from 
his own observations and partly quoted from the statement of Joseph 
L’Admiral, as follows: 
DATES. 
Entered pupa state. Butterfly appeared. Length of pupa state. 
July 8.. 
. '. . . .July 19. 
.11 
days. 
July 20. 
.August 5. 
.16 
c< 
August 19. 
.. 7 
u 
August 22. 
.September 2. 
.11 
u 
August 29. 
.September 7.. 
. 9 
u 
September 4. 
.September 23. 
.19 
a 
Professor French informs me that those he reared remained in the pupa 
state generally from six to eight days. 
My observations differ somewhat from either of these, showing the 
time to be shorter. A number of full grown worms, about twenty, 
were collected July 17, which were about to enter the pupa state; by 
the evening of the next day all were chrysalids. On the 22d of the 
same month, five days afterwards, a few butterflies made their appear¬ 
ance; the 23d a large portion appeared, and in a day or two more, 
all not parasitized had completed their transformations. 
It would appear from this that the pupa state is considerably 
shorter in the latitude of Southern Illinois than in that of New 
. York. 
As the insect winters in the pupa state, the chrysalids of the fall 
brood are not, as a matter of course, transformed * into butter¬ 
flies until the following season, from March to May, according to the 
latitude and season. The fact that one of Dr. Fitch’s specimens en¬ 
tered the pupa state August 21st, and the butterfly did not come out 
until December 8th; and one of L’Admiral’s which pupated September 
5th, did not come out until the 28th of May following; shows that 
in the same section some may be double-brooded while others may be 
but single-brooded. Or in more southern latitudes some double brooded 
and others three brooded. 
Miss Smith, in her address delivered before the Wisconsin Horti- 
cultura 1 Society, at Green Bay, states that “the butterflies” (of this 
species) are generally supposed to hibernate during the winter months(?) 
I presume that she intended to convey the idea by this language, that 
it is generally supposed this insect hibernates in the perfect or but¬ 
terfly state; so far, I have been unable to find any authority for this 
