845 
No. 145.] 
slight tooth upon its posterior face, and two short diverging club-shaped white 
bristles. Lower down upon the sides is a row of slight oblong elevations, one on 
each segment, below which the breathing pores form a row of minute round points, 
and below these an obtuse angular edge divides the lateral from the under side. On 
the under side are four longitudinal rows of short white club-shaped bristles, inclined 
backwards, two bristles at each point. Between the two inner rows of these bristles 
are two rows of small, elevated, wart-like pimples, which are the scars left by the 
pro-legs of the larva. The legs, antenna; and wings are enclosed apparently in a 
common sheath, the forked veins of these last forming faint elevated lines upon the 
smooth outer part of the sheath. The ciysalis varies in color. One of the specimens 
was bright pale green with a deeper green stripe along the middle of the back, and 
the long horns and a spot on the crown of the head dull brownish yellow. The other 
was pale brownish yellow throughout, with a black stripe along its middle. 
These insects remained at rest in their pupa state only six and 
eight days when they hatched moths, pertaining to the genus 
Pterophorus in the family Alucitidje and the ortjer Lepidoptera. 
The moths of this family are distinguished from all others by 
having their wings singularly cleft into two, three or more long 
narrow lobes, whence, they were termed Fissipennes or Split¬ 
winged moths by Latreille. The lobes are densely ciliated with 
fine hairs, which, along their inner margins are very long. They 
thus resemble the feathers of a bird, and have hence in English 
received the name of Plumes. Their legs are long and slender, 
and are furnished with long robust spines, of which there is a 
single one at the tip of the forward shank#, and a pair at the 
tip of the middle shanks, whilst the hind ones have a pair at their 
tips and another near the middle. 
The names of all the species belonging to this family are com¬ 
pounds ending with the word dactylus, meaning a finger; Lin¬ 
naeus at first, when but a half dozen species were known to him 
(Systema Naturae, 10th edition, 1758), having supposed they 
could all be distinguished merely by the number of the 
branches of their wings, he hence numbered them two-fingered, 
five-fingered, &c.; and at a later period, when two or more 
species were discovered which were alike in the number of 
their lobes, he named these wing-fingered, square fingered, &c. 
The species of which we are speaking, at each pair of spines, has 
tufts of scales of a tawny yellow color surrounding its hind legs 
