58 GENERAL ZOOLOGY 



may be an advantage rather than otherwise, making it 

 easy for any animal to distinguish them from edible species. 

 The brilliant colors are usually cited as an illustration of 

 warning coloration. 



The Viceroy Butterfly. Another butterfly of an entirely dif- 

 ferent genus (see page 107) and without any offensive odor, 

 — the viceroy (Basilar' chia archip'pus ; see illustration fac- 

 ing this page) , — closely resembles the monarch. The viceroy 

 belongs to a group of butterflies whose general body colora- 

 tion is blue and white, but instead of the livery of its rela- 

 tives it wears that of the monarch. It offers the best-known 

 illustration in North America of what is called protective 

 mimicrij, a term applied to those cases in the animal king- 

 dom in which a group of animals without disagreeable 

 qualities resembles, to a greater or less extent, animals pro- 

 vided with special means of defense. Protective mimicry 

 will be seen to differ from warning coloration in that the 

 latter is believed to protect an animal by marking it as a 

 source of real danger or unpleasantness ; the former is be- 

 lieved to protect by suggesting characters which have no 

 existence in fact. This explanation of the color of the 

 viceroy has been called in question, and observations are 

 wanting to show that the birds of the eastern United States 

 feed generally upon butterflies. Many cases of protective 

 mimicry are known among the butterflies of Africa and 

 South America. By the use of the term it is not meant, of 

 course, that there is anything conscious in the mimicry. 



Swallowtail Butterflies. The magnificent insects called 

 swallowtail butterflies, widely distributed over the world, 

 have received their common name on account of the shape 

 of the hind wings. They often exhibit, within the limits of a 

 single species, great variation in color, size, and even in 

 the shape of the wings. The variation in form, size, and 

 color between individuals of the same species is spoken of as 



