There is not in the whole group of caterpilrars a more innocent and harmless-looking object than the larva of Lagoa opercularis–especially just previous to the fourth moult. As it reposes curled upon a leaf, with its long, wavy, white silken hairs the sport of the slightest zephyr, it resembles nothing so much as a tuft of the finest white cotton, and seems almost to invite the touch of caressing fingers.