THE GENERA OF IIESPERIDI. 1375 



or with a sinuous lateral curve ; in the former case, comprising the higher 

 genera, the club is pretty stout; in the latter it tapers very gradually. 

 There is some variety in the form of the wing, some genera being pro- 

 vided with long tails to the hind pair, while others have the hinder edge of 

 the same wings scalloped or oddly excised. 



The eggs of this group are always longitudinally ribbed and trans- 

 versely lined, in which respect they are widely diiFerent from those of the 

 Paniphilidi. 



The caterpillars generally feed upon Leguminosae, but also upon a 

 variety of other angiosperms, and live in horizontal nests formed by bend- 

 ing over a portion of a leaf, and fastening it to the rest by distant broad 

 bands of silk, often so long as not to bring the different parts of the leaf in 

 contact ; or, later in life, they draw together several leaves in a similar 

 manner. 



The chrysalids are smooth and rounded, frequently of a mahogany 

 color, of a compact form, with scarcely any protuberances, and are en- 

 closed in a cocoon often made of the last larval nest more closely bound 

 together, or of a similar one constructed for the purpose, within which the 

 caterpillar weaves Y-shaped shrouds upon which to support the body. 



Table of the genera of Hesperidi, based on the egg. 



Vertical ribs not much higher on the arching shoulder of the egg than in the middle of the 

 sides; cross lines exceedingly frequent, breaking up the interspaces into cells more thaa 

 eight (9-11) times as broad as high. 

 Egg broadly truncate above, over a space about equal in width to half the width of the 

 egg; vertical ribs not over lifteen in number. 



With at most twelve vertical ribs. Egg an eighth broader than high Eudamus. 



With more than twelve vertical ribs. Egg a fourth broader than high Achalarus. 



Egg regularly domed above, with no portion truncate ; vertical ribs at least fifteen in 

 number. 



With sixteen to nineteen vertical ribs. Eggs less than a fifth broader than high 



Epargyreus. 



With about fifteen vertical ribs. Eggs a fourth broader than high Thorybes. 



Vertical ribs generally at least twice as high on the arching shoulder of the egg as in the 

 middle of the sides ; cross lines not so frequent as above, the cells being less than eight (4-7) 

 times as broad as high. 

 Vertical ribs less than twenty in number. 



The vertical ridging of the egg quite similar in thickness above and below, except 



that the ribs are often less numerous above Thanaos. 



The vertical ridging of the egg very dissimilar above .and below, some of the thin, com- 

 pressed ribs of the lower half of the egg being transformed .above to coarse, broad, 



rounded ridges of a unique appearance Pholisora. 



Vertical ribs more than twenty in number Hesperia. 



Table of genera, based on the caterpillar at birth. 



Head excessively large; dorsal shield of first thoracic segment conspicuous; first pair of thora- 

 cic legs conspicuously more corneous than the others. 

 First thoracic segment with only the dorsal shield corneous. 



Dorsal shield of first thoracic segment not nearly reaching the spiracles on the side.... 



Eudamus. 

 Dorsal shield of first thoracic segment reaching and including the spiracles on the side. 



Achalarus. 

 First thoracic segment completely corneous Thorybes. 



