PROMINENTS. 111 
dusky brown; the body is light brown, the thorax of a 
darker shade. With wings expanded they measure an inch 
and a quarter across. 
The female, which appears late in June, deposits her eggs 
in a cluster on the under side of a leaf. The tiny caterpillars 
at first only consume the substance of the under side of the 
leaf, but as they soon increase in size they devour the entire 
leaf. When not engaged in eating they huddle closely 
together and frequently completely cover the branch upon 
which they rest. While resting the posterior part of the 
caterpillar is always elevated. The young caterpillars are 
similar to, but lighter colored than the mature ones. These 
latter are greenish-yellow or yellowish-brown; the head and 
a prominent hump on the back of the fourth segment is 
coral-red. The body is striped longitudinally with dark 
brown or black lines; or, considering all the colors, with 
yellowish, white and dark lines. A double row of black 
spines extends along the back, and five black points are 
found on each side of the segments, three above the spiracles 
and two below. The back is marked with five narrow 
black lines; the ‘sides from the fifth to the tenth segment, 
inclusive, are whitish with black lines above the spiracles. 
The first three segments are spotted with black and white; 
the last segment is spotted with black. The legs are black ; 
the prolegs black and yellow, the last segments taper a 
little. When full grown the caterpillar is one inch and a 
quarter long. 
These caterpillars are gregarious, and soon defoliate the 
branch on which they were born. When handled they dis- 
charge a transparent fluid which possesses a peculiar acid 
smeil and which no doubt serves as a defense against ene- 
mies, especially birds, which can readily see these caterpillars 
so openly exposed in large numbers. 
When maturethelarve descend tothe ground,where they 
conceal themselves under leaves upon or slightly under the 
surface. Here they surround themselves with a very thin 
