The Moths and Butterflies 



447 



butterflies are found in the United States. Combined with them in the 

 family Papilionidae are two species of curious thinly scaled black- and red- 

 spotted white butterflies called parnassians, which live exclusively in high 



FIG. 639. Swallow-tailed butterflies, Papilio rutulus. (From life; one-half 



natural size.) 



altitudes in the Rocky and Sierra Nevada Mountains. Two more species 

 are found in high latitudes on this continent, namely in Alaska. Parnas- 

 sius smintheus (PI. V, Fig. 8; also Fig. 633) with four varieties is found 

 in both the Colorado Rockies and Sierra Nevada, while P. clodius, a larger 



