2 20 LLOYDS NATURAL HISTORY. 



sub-costal nervure four-branched, the second branch rising at 

 or a Httle before the end of the cell, the fourth running to the 

 tip or to the costa just before it, the upper radial nervule sepa- 

 rating from the sub-costal a little less than half way between the 

 cell and the tip. On the hind-wings, which are rounded, the 

 cell is longer and very pointed ; and the pre-costal nervule 

 is rudimentary. The claws are without appendages, but the 

 middle and hind tarsi in the females are said to possess two 

 delicate membranous three-jointed structures, which Reakirt 

 terms "Eupronychia." They are very delicate and easily lost, 

 and are therefore difficult to find except in very fresh specimens. 

 This is a purely American genus, and differs considerably 

 from Eurymus both in shape and pattern. The commonest 

 species is M. cesonia (Stoll) which inhabits the Southern United 

 States. It is a yellow species, shading more or less into orange, 

 but on the fore-wings the base is black, and the hind-margin 

 likewise, the centre of the wing being crossed by a broad 

 yellow band, on which the black discoidal spot is placed. The 

 inner side of the border is very irregular; on the costa it extends 

 narrowly to the black at the base, and on the inner-margin in- 

 wards for half its length ; but between, it forms a series of rect- 

 angles, the yellow colouring extending squarely into it in the 

 middle half way to the hind-margin. Another species, AT. 

 eurydice^ Boisduval, which is found in California, resembles 

 this, but is more of an orange-yellow; the fore-wings are beauti- 

 fully flushed with purple, and the hind-wings have no black 

 border. The female much resembles that of Colias rhamni^ 

 except in shape. Other species are found in Venezuela, Bolivia 

 &c. 



GENUS COLIAS. 



Colias^ Fabricius, in Illiger, Mag. f. Insekt. vi. p. 284 (1807); 

 Latreille, Consid. Generales, p. 440 (1810) ; id. Enc. 

 Meth. ix. pp. 10, 89 (18 1 9). 



