FAMILY PAPILIONID^E 



(THE SWALLOW-TAILS AND ALLIES). 



The butterflies of this group are provided in both sexes with six legs adapted to walking. 

 The internal vein of the hind wing is wanting, its place being taken by the submedian. Cat- 

 erpillars elongate, and in the genus Papilio provided with osmateria or protrusive forking scent- 

 organs, which, when excited, they thrust forth from the pouch back of the head in which they 

 usually lie concealed. Chrysalids in all the genera more or less elongate, attached at anal ex- 

 tremity to a button of silk, and held in place by a silk girdle, but 'never closely appressed tc 

 the supporting surface as is the case in the Erycinidce and Lyccenidoe. 



SUBFAMILY PIERIN^E 

 (THE YELLOWS, SULPHURS, AND WHITES). 



For the most part small or medium-sized butterflies, white or yellow in color, with dark 

 marginal markings. The eggs are spindle-shaped, marked with vertical ridges and horizontal 

 cross-lines. The caterpillars are cylindrical, relatively long, generally green in color, with longitu- 

 dinal stripes. The chrysalids are more or less pointed at the head, with the wing-cases greatly 

 developed on the ventral side, forming a more or less keel-shaped projection upon this surface. 



The subfamily is very large, and is well represented in the tropics of both the eastern 

 and western hemispheres. Certain genera are also widely distributed in the colder regions of 

 both the north and the south, among them the genus Colias, species of which occur from Green- 

 land to Patagonia and from the North Cape to the Cape of Good Hope. 



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