COLOR KEY TO THE COMMON BUTTERFLIES 



Based upon a Laboratory Exercise in Nature- Study at Cornell University 

 By Helen M. Hess 



A. Large butterflies — strikingly black and yellow. Hind wings 

 with tails. 

 B. Wings yellow, margined with black with four black bars 

 across the front wing. Expanse 3-3 >^ in. 



Tiger Swallowtail — Turnus form 

 BB. Wings black above, yellow beneath with broad diagonal 

 band of yellow from tip of front wing across base of hind 

 wing. A row of striking yellow sub-marginal spots 

 across hind wings and merging into diagonal band on 

 fore wing. Wing expanse 4-5 in. Giant Swallowtail. 

 BBB. Wings black, with double row of yellow marginal spots on 

 front wing, the inner row making a yellow band across 

 the hind wing. Wing expanse 2}4~s in. 



Black Swallowtail, male 

 AA. Butterflies mostly black. Wing expanse 2-3 >^ in. 



B. Hind wings with tails. 



C. Front wings black with pale spots near outer margin in 



single row and often rather inconspicuous. 

 D. Hind wings with blue spots or green inside the outer 

 row of yellow spots. 



1. Often six crescent shaped spots along the outside 



of the hind wing. The lower and especially 

 upper one orange. The others yellowish. 

 Tiger Swallowtail — Glaucus form. 



2. The pale marginal spots along outer margin of 



hind wing all the same color. An orange spot 

 at the middle of front margin and two orange 

 spots near inner angle of hind wing. 

 Green-clouded Swallowtail, female. 

 DD. The hind wings greenish and with only one orange 

 spot at inner angle of hind wing. 



Green-clouded Swallowtail, male. 

 DDD. Hind wings metallic dark blue. No orange spots on 

 upper side. On the lower side the marginal row of 

 spots orange below, pale above. 



Blue Swallowtail. 

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