ICO THIRD ANNUAL REPORT OF 



general plan of the Creator ; but viewed in the light of modern science, 

 and especially by that of the Darwinian development hypothesis, 

 they have acquired an immense significance. One of the most interest- 

 ing phases of this mimicry, and one which has only within the last few 

 years been brought to light, is the imitation by an otherwise defenseless 

 butterfly, of one whose great numbers and wide distribution indicate 

 that it enjoys peculiar advantages. This specific imitation of one but- 

 terfly by another is precisely of the same nature as the mimicking of a 

 vegetable or inorganic substance, and may consequently bejust as prop- 

 erly termed mimicry. Some authors seem to make a distinction between 

 this so-called mimicry and what is known as "protective resemb- 

 lance," while others again misconceive the true import of the word 

 "mimicry" as used in this connection. Thus, Maj. J. R. Muhleman in 

 an essay on "Mimicry in Insects," read before the Central Illinois Hor- 

 ticultural Society this winter, gave the word so broad an interpretation 

 as to apply it to the possum-playing of some insects, and even to the sup- 

 posed and far-fetched resemblances such as that of the female Canker- 

 worm to a plant-louse, and of the female Bag-worm to a Dipterous 

 maggot. True mimicry can only occur where it is of benefit to the 

 species, no matter whether the benefit be derived by enabling harm- 

 less species to avoid their enemies in one way or another; or by enab- 

 ling predaceous species to deceive their prey by assimilating the form 

 and colors of the latter. 



As already stated, the particular group to which our Archippus 

 butterfly belongs is a large one, and the species comprising it are 

 very numerous. They are especially abundant in South America, and 

 like our own species, they all possess a pungent odor which seems to 

 pervade all the juices of their system. So much is this the case that 

 according to Mr. Wallace,* when an entomologist "squeezes the 

 breast of one of them between his fingers to kill it, a yellow liquid 

 exudes which stains the skin, and the smell of which can only be got 

 rid of by time and repeated washings." The wings of these butter- 

 flies, as may be seen by referring to Figure 63, are rather longer than 

 usual, but their flight is comparatively slow, and they do not dodge 

 and zig-zag about with sudden skips and jerks as the "Skippers," 

 (Hesperid.e,) are known to do. They furthermore possess no adap- 

 tive coloring to protect them during repose, for they take no pains to 

 hide themselves, and their colors are bright, and those of the under- 

 side as conspicuous as those of the upper. 



Hence we cannot assume that they are enabled, by their pecu- 

 liar mode of flying, to escape to a great extent those cannibal 

 animals that would otherwise catch and devour them; and if we pro- 

 pose to account for their prodigious abundance at all, we are driven 

 to have recourse to some other hypothesis. Indeed, so far is it from 

 being the case that it is their mode of flight which enables them to 



Contributions, etc., p. 78. 



