380 THE STUDY OF INSECTS. 



(tel-a-mon'i-des). This form is a little larger than marcellus 

 and has tails nearly one third longer ; these tails are bordered 

 with white on each side of the distal half or two thirds of 

 their length. 



(3) The Summer Form, Iphiclides ajax ajax. The sum- 

 mer form is still larger, expanding from three and two tenths 

 inches to three and one half inches, and has tails nearly two 

 thirds longer than the early-spring form. 



The life-history of this species has been carefully worked 

 out by Mr. W. H. Edwards. He has shown that there are 

 several generations each year, and that the winter is passed 

 in the chrysalis state. But the early-spring form and the 

 late-spring form are not successive broods ; these are both 

 composed of individuals that have wintered as chrysalids, 

 those that emerge early developing into marcellus, and those 

 that emerge later developing into telamonides. All of the 

 butterflies produced from eggs of the same season, and there 

 are several successive broods, are of the summer form, ajax 

 ajax. 



The larva feeds upon papaw (Asimina). This insect is 

 found throughout the eastern half of the United States 

 except in the extreme north. 



Subfamily PARXASSIIN.E (Par-nas-si-i'nae). 

 The Parnassians (Par-nas 1 si-ans). 



The Parnassians differ from the Swallow-tails in lacking 

 the tail-like prolongations of the hind wings and in that the 

 ground-color of the wings is white ; but resemble them in 

 the general plan of the venation of the wings, and in pos- 

 sessing similar scent-organs (osmateria) in the larval state. 

 The wings of the butterflies are usually conspicuously marked 

 with black spots and shades, and with red spots. Only four 

 species have been found in North America. These belong 

 to the genus Parnassius (Par-nas'si-us). They are found only 

 on high mountains or far north. 



