The Life-History and Anatomy of Butterflies 



first of which, nearest the body, is called the coxa, with 

 which articulates a ring-like piece known as the trocbanter. To 

 this is attached the femur, and united with the femur, forming 

 an angle with it, is the tibia. To the tibia is attached the tarsus, 

 or foot, the last segment of which bears the claws, which are often 

 very minute and blunt in the butterflies, though in moths they are 

 sometimes strongly hooked. The tibise are often armed with 

 spines. In some groups of butterflies the anterior pair of legs is 

 aborted, or dwarfed, either in one or both sexes, a fact which is 

 useful in determining the location of species in their systematic 

 order. 



The Wings. The wings of butterflies consist of a framework 

 of horny tubes which are in reality double, the inner tube being 



FIG. ;6. Magnified representation of 

 arrangement of the scales on the wing of a 

 butterfly. 



FIG. 37. Androconia from 

 wings of male butterflies: a, 

 Neouympha enrytus', b, AY- 

 gynnis aphrodite; c, Pirn's 

 oleracea. 



filled with air, the outer tube with blood, which circulates most 

 freely during the time that the insect is undergoing the process of 

 development after emergence from the chrysalis, as has been al- 

 ready described. After emergence the circulation of the blood in the 

 outer portion of the tubes is largely, if not altogether, suspended. 

 These horny tubes support a broad membrane, which is clothed 

 in most species upon both sides with flattened scales which are 

 attached to the membrane in such a way that they overlap one 

 another like the shingles on a roof. These scales are very beau- 

 tiful objects when examined under a microscope, and there is 

 considerable diversity in their form as well as in their colors. The 



18 



