HOW TO KNOW THE BUTTERFLIES 



form which is smaller than those described above, and of a 

 dark color ; this form is easily recognized by the color of the 

 band bearing the eye-spots on the fore wings, it being reddish 

 yellow. 



Caterpillar. — Length one and one-third inches. Green 

 in color with two lighter green or yellowish lengthwise stripe.3 

 along each side. The body is covered with down but is other- 

 wise naked. The slender tail ends in a shallow fork. 



Food-plant. — Grass. 



The Blue-eyed Grayling. — The blue eyes of 

 this grayling are rather disappointing, partly be- 

 cause they are mere dots in the large black eye- 

 spots, scarcely noticeable from above, and partly 

 because they are usually lavender instead of blue ; 

 however, on the lower sides of the wings the blue 

 eyes are well worth looking at. Above and be- 

 low the blue iris has a pupil of white at its cen- 

 ter. The first thing that attracts the eye to this 

 butterfly is never blue eyes, but rather the large 

 yellow band on the outer half of the front wing 

 against which the round black spots, each a true 

 " bull's-eye " in its appearance, shows off to great 

 advantage. 



The blue-eyed grayling is most careless as to 

 the number of its decorations. Usually two eye- 

 spots on the front wing are reproduced with 

 large blue centers on the lower side ; but one 

 of our specimens shows these ocelli with white 



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