818 
[AsSEMBLr 
apex of the lower jaws, a short obtuse projection with minute hairs at its tip. The 
antennas are conical and three-jointed, the last joint minute and the second one 
armed exteriorly with a short bristle. At their base on the under side of the head 
are three or four dilated punctures. There are a few scattered brown bristles upon 
the head and also upon each of the other segments; those on the third, fourth, 
twelfth and thirteenth segments are arranged in transverse rows, and on the other 
segments they are placed symmetrically and arise from faint smooth wart-like spots. 
The second segment is tinged with yellowish above and has a breathing pore upon each 
side. The two next segments are somewhat shorter than the following ones and are 
destitute of breathing pores. These three segments each bear a pair of conical legs 
ending in a black polished claw. The remaining segments except the two last show 
a faint stripe, at least posteriorly, upon the middle of the back, and each has also a 
transverse impressed line in the middle and a breathing pore upon each side. The 
two last segments, which perhaps should be regarded as one double segment, are 
narrower, shorter, and retractile, shutting into each other and into the segment for¬ 
ward of them, like the joints of a telescope. Beneath is a pair of prolegs upon the 
seventh and three following segments, which scmcely protrude from the general sur¬ 
face, but are very perceptible from their soles being furnished with two transverse 
rows of minute black hooks, about twelve hooks in each row; and the last segment 
has a single shorter row of six similar hooks upon each side. 
The young worm is quite similar in its details to the mature one; its breathing 
pores upon the second and the twelfth segments, however, are much larger and more 
obvious than the intervening ones. 
The Pupa enclosed within its follicle is at first white, the wing and leg sheaths and 
the thorax being slightly tinged with tawny yellow. The breathing pores form a 
row of tawny dots along each side of the abdomen, each segment of which has a row 
of little sharp-pointed teeth on its anterior and a second shorter row of smaller ones 
on its posterior margin, extending half way around, from one row of breathing pores 
over the back to the opposite row, these teeth being of a pale tawny color and direc¬ 
ted backwards. The three apical rows of these teeth, however, have no intervening 
rows of smaller ones. At the tip is a row of eight larger teeth extending entirely 
around. It is by means of these teeth that the pupa when ready to disclose tho 
winged fly crowds itself forward, out of its follicle. All the teeth become longer and 
morje sharp-pointed as the pupa approaches maturity, and the whole of the surface 
now assumes a pale tawny yellow Color, with a darker ring at each of the sutures. 
The mature insect, like most of the species of butterflies and moths, varies con¬ 
siderably in its size. It measures from one-halfto three fourths of an inch in length, 
and the wings when extended are from 0 80 to 1 30 across, the female being more 
variable in its size than the male and furnishing both the smallest and the largest in¬ 
dividuals. The wings of the fen,ale also measure more than those of the male when 
their bodies are of equal length, the more thick and heavy body of the female plainly 
requiring larger wiugs to sustain it in the air. 
The male is of a deep steel blue color with various sulphur yellow marks and has 
a glossy lustre like that of satin. The antennae are black, less than half as long as 
the body, abruptly curved outwards at their tips and densely fringed along their inner 
