The Life-History and Anatomy of Butterflies 



thought, before the truth was known, to constitute a separate 

 species. 



Albinism and Melanism.— Albinos, white or light-colored 

 forms, are quite common among butterflies, principally among 

 the females. On the other hand, melanism, or a tendency to the 

 production of dark or even black forms, reveals itself. Melanism 

 is rather more common in the case of the male sex than in 

 the female sex. The collector and student will always endeavor, 

 if possible, to preserve these curious aberrations, as they are 

 called. We do not yet entirely understand what are the causes 

 which are at work to produce these changes in the color, and all 

 such aberrant specimens have interest for the scientific man. 



Monstrosities.— Curious malformations, producing monstrosi- 

 ties, sometimes occur among insects, as in other animals, and 

 such malformed specimens should likewise be preserved when 

 found. One form of malformation which is not altogether un- 

 common consists in an apparent confusion of sexes in specimens, 

 the wings of a male insect being attached to the body of a female, 

 or half of an insect being male and half female. 



Mimicry.— One of the most singular and interesting facts in 

 the animal kingdom is what has been styled mimicry. Certain 

 colors and forms are possessed by animals which adapt them to 

 their surroundings in such wise that they are in a greater or less 

 degree secured from observation and attack. Or they possess 

 forms and colors which cause them to approximate in appear- 

 ance other creatures, which for some reason are feared or disliked 

 by animals which might prey upon them, and in consequence of 

 this resemblance enjoy partial or entire immunity. Some butter- 

 flies, for instance, resemble dried leaves, and as they are seated 

 upon the twigs of trees they wholly elude the eye. This illustrates 

 the first form of mimicry. Other butterflies so closely approxi- 

 mate in form and color species which birds and other insects will 

 not attack, because of the disagreeable juices which their bodies 

 contain, that they are shunned by their natural enemies, in spite 

 of the fact that they belong to groups of insects which are 

 ordinarily greedily devoured by birds and other animals. A 

 good illustration of this fact is found in the case of the Disippus 

 Butterfly, which belongs to a group which is not specially pro- 

 tected, but is often the prey of insect-eating creatures. This 

 butterfly has assumed almost the exact color and markings of the 



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