THE GENUS BASILARCHIA 23 



tare and its habits of life, which hitter are very 

 largely, perhaps almost absolutely, dependent on 

 its structure ; its tastes and its propensities ; its 

 fears and its devices to circumvent its enemies ; 

 all its instincts, which are to a great extent, pos- 

 sibly wholly, the entailment of ancestral habits ; 

 its very attitudes, whether at rest or in motion. 

 Its advantages and its disadvantages are thus 

 alike its legacy ; so too the peculiar means it em- 

 ploys to disembarrass itself of these disadvantages. 

 This is especially true of the insect in its ear- 

 lier stages, where freedom to change the immediate 

 surroundings is exceedingly limited or altogether 

 impossible, except so far as there is foresight, or 

 an instinct marvelously akin to foresight, on the 

 part of the creature in an antecedent stage. 



It is of more than usual interest to study the 

 means of self-preservation in the genus Basilarchia, 

 since there is hardly another genus of our butter- 

 flies where throughout its entire life the insect is 

 apparently so exposed to its enemies. They are 

 all, of their kind, conspicuous objects even to our 

 dull eyes, and more than that they are, with the ex- 

 ception of the chrysalis, always found in unusually 

 conspicuous situations. How then do they manage 

 to escape their keen-sighted foes, the birds ; or 



