CHRYSALIS, krTs'a-111, the pupa stage in butterflies, succeeding the caterpillar. During They either suspended head downward by the tall, or rest horizontally, with a thread pass ing around them to hold them securely. Many, if not most, chrysalides are protected from ob servation by their colors, which' harmonize with the color of the object to which they are at tached. Thus, the chrysalis of the milkweed butterfly (Anosia archippus) which is suspended, among the pale-green leaves of the milkweed' and does not hibernate, is of a pale-green tint; while those of Papilio turnus, or of Pieris, are gray, and so spotted with light and dark marks as to harmonize with the neutral tints of the boards or fence to which they are attached. These colors and markings are apparently due to the effects of light and shade. These tints are determined at the period when the caterpil lar is about to pupate, or become a chrysalis, when the integument is soft and moist. Poul
ton found, by subjecting the partly formed chrysalis to artificial surroundings of different colors, that the breeding boxes, when lined with black paper, produced dark chrysalides; when lined with white, light-colored, or green ones, or when lined with gilt, they produced chrysalides of a golden color, more completely so than occurs in nature.
Certain chrysalides have been found to ex hibit negative phototropism (q.v.) ; that is, are directly sensitive to light. They will, while sus pended by the tail, change their position if sun light strikes them, and move so as to keep in the shade, from a pendant to a horizontal posi tion, through an angle varying in different spe cies of from 45 degrees to 70 degrees or even 90 degrees. Too much light, especially direct sunlight, seems to he injurious to them, and the movement is one of protection.