588 
Annual Report of New York 
and fastened at its tij>, it moves this part of its body around and 
around, in a rotary manner as it were, thus crowding against the pellet 
of old skin, dislodging it from its former place, and gradually breaking 
it off from its connection with the little bundle of silk threads. It 
continues this motion some little space of time to accomplish this 
purpose, over a halt minute I should judge it to have been, in the 
instance which I witnessed. At length the crumpled mass, having 
become rolled into a little wad no larger'than a kernel of allspice, 
becomes entirely detached and falls to the ground. 
As yet the pupa retains the shape of the larva, being thickest 
anteriorly and gradually tapered to the tip, without any angular pro¬ 
jections upon the back, only the horn at the anterior end and the wing 
sheaths having their pupa development. But the protuberance upon 
the back of the thorax case soon begins to appear, and shortly after 
this a slight angular projection becomes perceptible upon each side 
of the middle of the back. These gradually become more prominent, 
and in a short time the whole surface becomes molded into its normal 
pupa form. 
The chrysalis or pupa of this as of many other butterflies has such 
a singular form that persons not versed in entomological science will 
deem its back to be its under side. It is what is technically termed a 
naked, suspended, angular pupa; that is, it is not inclosed in a cocoon 
or other covering; it hangs suspended in a loop, and its surface presents 
angular processes and projecting points. Along its under side it is 
smooth and nearly straight from end to end, but its back is much bulged 
and uneven, with angular ridges and projections. It is of a white or 
yellowish -white color, frequently with stains of brown on some parts 
of the surface, and with numerous black dots of different sizes, the 
most of which are placed symmetrically. 
The top a is about 0.70 long, 0.15 wide and 0.24 high. It is divided into twelve 
segments, the sutures between most of them being quito conspicuous. The first 
segment or head case is prolonged forward into a prominent conical point which is 
curved gently upward and is bluntly rounded at its tip. Near its base on the upper 
side are two small projecting points which are usually black. From each of these an 
elevated line extends obliquely backward and inward to the anterior end of a promi¬ 
nent keel-like ridge along the middle of the occiput which is the anterior end of the 
prominent dorsal ridge, and is of a black color. The second segment or thorax case 
is elevated in the middle of the back into a very prominent stongly compressed nose¬ 
like ridge, which is rounded at the summit and descends backward in a straight or 
nearly straight line, a slight notch usually occuring toward its end, made by the suture 
between this and the third segment. The third segment is short, the ridge upon its 
middle is black, and it frequently shows four dots in a transverse row on its anterior 
part, the outer dots being longer. The fourth segment is equally or more short than 
