DEFINITION OF THE COLIAN^. 89 



under wings have no groove for the body. Their geo- 

 graphic distribution is similar to that of the last family, 

 except that the genera of the Old World are in most 

 cases different from those of the New, and there are as 

 many species in temperate as in tropical latitudes. 



(80.) The Coliance, or yellows, exhibit a uniformity 

 of colour seldom met with so decidedly prevalent in all 

 the species. They are of a rich straw colour or bright 

 yellow, entirely destitute of bands or spots ; but the 

 under surface is variegated with minute dots, and gene- 

 rally marked by one or two small central silver spots. 

 From the great similarity which prevails, the species are 

 not readily distinguished. The form of the perfect in- 

 sect, however, is very peculiar : its structure is thick 

 and robust ; the wings triangular, with the angles either 

 very slightly rounded or decidedly acute : no other but- 

 terflies in this family possess these characters, which all 

 indicate that boldness and vigour of flight belonging to 

 the group. The antennae also are peculiar ; they are 

 very gradually thickened towards the tip, where they 

 end abruptly and without any compression : the ante- 

 rior feet, although provided with claws, are much shorter 

 than usual; and the lower wings form an imperfect 

 groove for the body. Several species belonging to the 

 genera Gonepteryx and Eurymus occur throughout 

 Europe, and some of these inhabit Britain ; but the ty- 

 pical form is chiefly confined to the tropical latitudes 

 of both hemispheres, where they are found in prodigious 

 numbers: they are, in fact, migratory insects, and re- 

 present the swallows in their own tribe. 



(81.) Of the Lyccsnince we can say but little, since we 

 know not the exact extent of the group : they are, how- 

 ever, immediately distinguished by their large under 

 wings, which are as long, and always much broader, 

 than the upper : the sexes differ so materially, that 

 closet naturalists have not only described them as 

 separate species, but have imagined they belonged to 

 different genera. In structure and appearance they 

 resemble the Heliconidce ; but their anterior feet are 



