108 



SECOND ANNUAL REPORT OF 



South as Lake Winnepesaugee. It having since been taken at Ban- 

 gor, and at other points in Maine ; in certain parts of New Jersey, 

 and the past year around Boston and New York. 



It was in all probability introduced into this country in the egg 

 state, for the eggs are deposited on the underside of the leaves, and 

 there is nothing more likely than that a batch may have been thrown 

 with refuse leaves from some vessel, and that after hatching the 

 young larvae managed to find suitable food close by. 



The larva (Fig. 77, «), is pale green, finely dotted 

 with black, with a yellowish stripe down the back, and 

 a row of yellow spots along each side in aline with the 

 breathing holes. When about to transform, it leaves 

 the plant upon which it fed, and shelters under the 

 coping of some wall or fence, or on anything that may 

 be conveniently at hand, and changes to a chrysalis 

 (Fig. 76, h) which though variable in color, is usually 

 pale green, speckled with minute black dots. The in- 

 sect passes the winter in this state and as with the two 

 indigenous species, there are two broods each year. 

 The butterflies have the bodies black above, with the wings 

 white, and marked as in the accom- 

 panying cuts ; the female (Fig. 78) 

 being distinguished from the male 

 (Fig. 79) by having two round spots 

 (sometimes three) instead of only one 

 on the front wings. Underneath, both 

 sexes are alike, there being two spots 

 on the front wings and none on the 

 hind ones, which are yellowish, sometimes passing into green. The 

 6pecies varies very much, and there is a specimen in my collection in 

 which all the spots are so nearly obsolete above, that if it were not 

 [Fig. 79.] for the characteristic under-surfaces, 



it could scarcely be distinguished from 

 the Potherb Butterfly. There is also 

 in England a variety of the male sex 

 which has the ground-color canary 

 yellow instead of white, and curiously 

 enough, this same variety has been 

 taken in this country. 

 Although some caterpillars arepoly- 

 phagous, feeding indiscriminately on a great variety of plants, yet 

 most ol them are confined to plants of the same botanical family, or 

 at all events of the same natural order. Such is the case with the 

 two indigenous cabbage butterflies above mentioned, for they are not 

 known to go beyond crucilerous plants for food. The Rape Butterfly 

 has a less epicurean palate however, and departs from this rule, inas- 



