3l4 Canadian Butterflies. 



•which occupies about a fourth of their length, the head has no 

 frontal tuft ; forewings sub-triangular, and the posterior rounded ; 

 the discoidal cell of the hind wings closed ; thorax thick ; body 

 shorter than the wings ; tarsal ungues bifid ; fore legs alike in 

 both sexes. Their flight is very rapid, and they are difficult to 

 capture. The caterpillars naked, elongate, cylindric, very finely 

 setose and tubercled. The chrysalides rather short, sub-angular, 

 gibbous, slightly beaked in front, attached by the tail, and by a 

 girth behind the thorax. 



The iarvse feed on leguminous plants. 



This is one of the most natural genera of diurnal lepidoptera ; 

 the color is always some shade of yellow or orange, more or less 

 bright, and frequently tinged with green. All have a portion of 

 the wings marked with black ; the forewings also exhibit a black 

 discoidal spot, and the posterior a central spot, which is orange 

 above, and generally silvery beneath. The palpi and antennse are 

 always reddish or rosy. 



The general resemblance between the species and some being 

 extremely subject to variation, has led to much confusion in their 

 synonomy. The species are not very numerous, and none of them, 

 even of the exotic kinds, beyond the middle size. This genus is 

 found in all the temperate parts of the globe, but they are not 

 known to inhabit the equatorial regions of the two continents. 

 All those which are known come from Europe, Siberia, Cape of 

 Good Hope, Barbary, ISTorth America, Mexico and N'ew Holland, 

 Six or seven species inhabit North America, of which two are 

 found in Canada, viz : — C. edusa and Philodice. We also describe 

 a third, C. chrysotheme which occurs in the State of New York. 

 Two or three species inhabit Labrador and the Hudson's Bay 

 Territories, and the remaining one the Southern States. 



Species 1. — Colias Edusa. The Clouded Yellow. 



Colias Edusa, Boisduval and Leeonte, Ico. &c., des Lepidop- 

 teris, &c., de I'Amerique Sept. t. 1, p. 59. Paris, 1833. 



Colias Edusa, Duncan, Brit. Butterflies, p. 103, pl. v, fig. 2. 

 Edinburgh, 1835. 



Colias Edusa, Kirby, Fauna Bor. Amer., (Insects) p. 287. 

 Norwich, 1837. 



Colias Edusa, Westwood and Humphrey, Brit. Butterflies, p. 

 15, pl. 11, fig. 1-4. London, 1841. 



Papilio Edusa, Fabricius, Mant. Ins., t. 11, p. 23, n. 240. 

 Hafhice, 1787, &c. 



