LIBYTHEINAE: THE GEKUS HYPATUS. 



755 



subtropical region on the Atlantic side of the continents, north of the 

 equator. One species occurs in northern South America, two others in 

 the Antilles and Central America, a fourth is known only from tlie Mexican 

 border of the United States, and is probably Mexican, while the northern- 

 most inhabits the United States, and especially its southern portion, but 

 has been found in two or three instances in New Enjrland and its neifh- 

 borhood. The species of the genus therefore appear to stretch in belts 

 from the equator to Latitude 45'' N. 



Characteristics. The butterflies are rather below the medium size but 

 are very striking in appearance ; the palpi are considerably more than 

 half as long as the whole body, the wings are very strongly angulated, 

 the fore pair especially strongly excised just below the lowest subcostal 

 nervule. They are dark brown above, the hind wings furnished with a 

 broad, fulvous patch across the middle, the fore wings with similar but 

 longitudinal patches, one in the cell and the other following the lower 

 median nervule ; in the apical half of the same wing are three white spots 

 forming a large triangle. Beneath, nearly the whole basal half of the fore 

 wings is fulvous, and the rest dark brown with a repetition of the white 

 spots ; the hind wings beneath are of changing shades of brown, specked 

 with blackish, and often varied with metallic tints. 



The butterflies are probably polygoneutic, and hibernate in the imago 

 state. The larva is cylindrical, slender, naked, green, with lighter or 

 darker dorsal and lateral stripes. The chrysalis is well rounded, the head 

 not produced but angulate, the dorsum of thorax and abdomen consider- 

 ably arched Avith a rather strong constriction between ; it is green with 

 some inconspicuous, pale yellow, longitudinal stripes, following the cari- 

 nate parts of the body. 



Relationships. The genus is the only one of its subfamily found on 

 this continent, and the species have been universally regarded by natural- 

 ists as congeneric with those of the Old World. This appears to be 

 merely the result of their all belonging to a remarkable and isolated type 

 of butterflies and not to any careful study of their structure. I have not 

 been able to study the Asiatic species, but the European and African are 

 certainly distinct from the American forms. I would call attention to 

 the abruptly lobate front margin of the hind wing in the European species 

 (Libythea proper), and the close approximation of the third and fourth 

 superior subcostal nervules of the fore wings at their origin, to the gradu- 

 ally incrassating antennae, in which the club can scarcely be separately 

 distinguished, but may be said to occupy half the length of the antennae, 

 to the coarser and, owing to the comparative brevity of the apical joint, 

 the somewhat shorter palpi, and finally to the deeply bifid termination of 

 the eighth abdominal segment in the male, with the irregular and thorny 

 clasps, which are in striking contrast to those of Ilypatus. It may also be 



