1854 BUTTERFLIES BEYOND NEW ENGLAND. 



nights hide in the leaves ; they are very susceptible to cold, prolonged 

 darkness or confinement of any kind ; when not feeding " they either rest 

 upon the leaves in full sunlight, or bask upon the stones and coarse gravel 

 among which their food plants grow. These stones are often heated by 

 the sun during the day to a temperature of 90" to 100" F., and retain a 

 part of the warmth over night." (Mead.) 



HESPERIDAE. 



TRIBE HESPERIDI. 



RHABDOIDES* gen. nov. 



Imago. Head large, compact, sessile, the front mesially and strongly tumid, much 

 surpassing the front of the eyes, the lower edge marginate; vertex depressed, nearly 

 flat. Eyes very large, very full, circular, naked. Palpi short and rather small, the 

 basal joint tumid, larger apically than at base, produced apically on the outer side, no 

 longer than broad; middle joint sub-cylindrical, rounded at each end, less than four 

 times as long as broad ; apical joint minute, ovate or subconic, not so long as the width 

 of the middle joint. Antennae separated at base by three times the width of the basal 

 joint, exclusive of the crook a fourth longer than the abdomen, composed of about 

 forty-eight joints of which about twenty-eight form the very gradually incrassated, 

 cylindrical or elongate, fusiform club, which is nearly as long as the stalk and bent 

 rather beyond the middle, the crook tapering gradually to a delicate pointed tip ; in the 

 middle of the stalk the joints are about three times as long as broad; on the broadest 

 part of the club about twice as broad as long. 



Fore wings shaped as in Achalarus, with which also the neuration essentially agrees. 

 Internal nervure delicate but distinct, short, distant from the submedian nervure and 

 running into it. Hind wings rounded triangular, considerably longer than broad, es- 

 pecially in the male where the submedian area is produced, so that the outer margin 

 is more rounded in the female than in the male ; in both it is gently crenulate between 

 the nervures; neuration as in Achalarus but with the subcostal and second median fork 

 almost equally distant from the base. 



Fore femora slightly longer than hind femora, nearly twice as long as fore tibiae, 

 and almost as long as fore tarsi ; first fore tarsal joint fully as long as the rest of the 

 tarsus. Hind femur three-fourths the length of the hind tibia and half as long as 

 tarsi; first joint of tarsus equalling the remaining joints together, the fifth equal to 

 the fourth, all clothed beneath with three rows of slender spines, the apical ones of 

 each joint larger than the others. Claws very small and delicate, bent in the middle 

 and finely pointed. Paronychia well developed, the upper lobe claw-like and as long as 

 the claw, tapering but little, the other as long, forming a broad inferior flap. 



The Illustrations of the early stages by Abbot do not permit one to mention any 

 generic features, excepting that the chrysalis is exceptionally slender and tapering for 

 one of this group of Hesperidi. 



This is a small group composed of a few species only, found exclusively 

 in America and especially in the tropics ; how far it ranges I am unable to 

 say, but in the United States the only species known is that here described, 

 whose early stages were figured long ago by Boisduval and LeConte from 

 Abbot's drawings, and which give us all that is known of them. 



'poipSos, a stripe. 



