84 THE BUTTERFLIES OF THE WEST COAST 



i8. Papilio Albanus. 



No figure. 

 This is said to be the high mountain form of Eurymedon, 

 "smaller in size, of clearer white ground-color ; tails long and nar- 

 rower : marginal spots nearer the margin." The facts are that 

 Eurymedon, of any form that I have ever met, seldom comes 

 lower down than 2,000 feet, in California ; possibly it may fly at 

 lower altitudes in the north ; and in the mountains about Lake 

 Tahoe it flies plentifully enough at 10,000 feet, at which locality 

 I have taken them, and apparently they would go far higher, if 

 there were any peaks for them to fly upon ; and from my exam- 

 ples, from widely different places, the characters given above do 

 not hold good, and I consequently regard this varietal name as of 

 little or no value. 



19. Papilio Rutulus. 



Plate III; Figure 19. Southern California, May, 1885; 

 Author. 



Rutulus is the common and well-known yellow swallow-tail of 

 the West Coast. It has a wide range north and south, from 

 Alaska to Mexico, and from west to east as well, flying from tide- 

 water of the Pacific Ocean to the Rocky Mountains of Colorado. 



It is essentially a plains species, living in the valley low-lands, 

 and flying about the willow copses, and along the banks of 

 streams where the water-willows grow, for it is upon the willow 

 leaves that the eggs are laid, and upon which the caterpillars feed ; 

 and the fine, great butterfly goes sailing up and down the willow- 

 bordered lanes, as luxuriously as though it owned the country; 

 as if, like Crusoe, it was monarch of all it surveyed, a grand but- 

 terfly ; yet, although they like to strut and to show off their ample 

 wings, they like as well to feed on the wild blossoms, or on the 

 flowers of the cultivated alfalfa, so that they are not very difficult 

 to take, when once you know their ways. 



The eggs are laid singly on the underside of young willow 

 leaves, and as soon as the caterpillar is large enough, it draws the 

 edges of the leaf together with threads of silk, and so forms a tube 

 or cone in which it lies hidden all the time, only poking its head 

 out to feed. On this account the larvse are difficult to find. 



Sex-marks, as already explained. 



Food-plant : Willow. 



