MOTHS AND BUTTERFLIES. 497 



the butterflies which imitate the protected species had acquired their presets marvel- 

 lously deceptive appearance through variation and natural selection, in order to be mis- 

 taken for the protected kinds, and thus to escape being devoured." 



The true ParnnssiiuB may be characterized as having the " antennae very short, the 

 wings of a parchment-like texture, occasionally denuded of scales, the abdomen very 

 stout and hairy, furnished in the females of nearly all the genera with a singularly 

 formed corneous pouch, the larva smooth, thick, cylindroid, with small tubercles, 

 slightly hairy, with a Y-shaped furcate tentacle on the first segment, the chrysalis pow- 

 dered with bluish efflorescence, enveloped in a light tissue of silk, and sustained by 

 transverse threads." 



The genus Parnassius has the wings mostly white, tinted occasionally with yel- 

 lowish, in one very rare and beautiful species, P. euersmanni, the ground color being 

 bright lemon-yellow. The ornamentation is composed of crimson spots of various 

 sizes, generally surrounded by black rings, and occasionally with a white pupil, and on 

 the margins black blotches of various shapes and sizes. One section of the genus wants 

 the red spots, and herein approaches the Pierinag, especially those forms nearest to P. 

 cratcegi. The Parnassians are all lovers of mountain regions, and are rarely found below 

 fifteen hundred feet elevation, while their range is confined to the northern hemisphere, 

 none of them having been found south of 28 of north latitude. The best-known 

 species is P. apotto, which is abundant throughout Switzerland, the Pyrenees, and the 

 Cevennes, being found, though rarely, in Sweden and Norway. P. phoebus is also 

 found in the Alps, and its varieties or offshoots extend through the Ural Mountains 

 and the Altai, to Kamschatka, one of them crossing Behring's Straits, and making its 

 home in the Rocky Mountains, where it is very abundant, having been described 

 as P. smintJieus. A variety, in which the spots are yellow instead of red, and 

 which has been known as P. behrii, is peculiar to the Sierra Nevada and the coast 

 range of California. I have said in another place : " It is a remarkable fact that P. 

 behrii (always with yellow spots) is found in California, occasionally in large numbers, 

 while no example of the typical P. smintheus (with red spots) has as yet been met with 

 within the borders of that state. It may therefore be reasonable to conclude that, in 

 the migration of the species known as P. smintheus, certain individuals, a little differ- 

 ing from the type, divided themselves from the main body, and passed down the moun- 

 tain chain of the Sierra into California, here meeting certain conditions, as yet only 

 vaguely known to us, which tended to the development of yellow rather than red 

 spots, at the same time eliminating some of the black patches on the wings of the typical 

 form, and producing the examples which we now recognize under the name of P. 

 jBehrii." Three other species are known to inhabit this continent. Altogether about 

 thirty-five species of the Parnassius are now known. 



To the PapilioninaB belong some of the giants of the butterfly world, forms which 

 not only attract the eye by their beauty, but astonish by their size and by their powers 

 of flight. First we have to consider a group of insects which are associated under the 

 generic name Papilio. But it must be confessed that this contains some very incon- 

 gruous forms, and needs careful revision, and, above all things, a study of the earlier 

 stages. Jacob Htibner began the work of separating the genus about the beginning 

 of the present century, and has been followed in this country by Mr. S. H. Scudder, 

 who has assigned our North American species to not less than six genera, all of which, 

 according to the last-named author, are of equal independent value. However Mr. 

 Scudder's conclusions may be contested, it is certain that the larvaa as well as the 

 VOL. ii. 32 



