Subfamily Parnassiinæ (the Parnassians)
This peculiar group of butterflies is classed with the Papilionidæ because the internal vein of the hind wings is always wanting, a characteristic of all papilionine genera. The caterpillars are not provided with osmateria, or offensive scent-organs, and pupation takes place upon the ground among loosely scattered leaves which are interwoven by the larva with a few loose strands of silk. The insects are mainly inhabitants of the mountain regions of the northern hemisphere.