BLUES. 



131 



hind wings is a series of black spots parallel 

 with the hind margin ; these alternate with 

 the wing-rays : in the female the wings are 

 pale smoky brown, with a very indistinct, 

 median, transverse, linear, black spot, and 

 also a series of obscure spots parallel with the 

 hind margin : in the hind wings these spots 



44. CHALK-HILL BLUE (lrycH-.no, Corydon). 

 Male and Female. 



have a compound character orange above, 

 black in the middle, and white below ; the 

 fringe is spotted. The under side is gray in 

 the males, gray-brown in the females; all the 

 wings have a transverse median discoidal 

 spot ; in the fore wings this is black with a 

 white circumscription ; in the hind wings it 

 is white with a very slender black median 

 line : on the fore wings are nine other black 

 spots, and on the hind wings eleven, all of 

 which have a white circumscription : there is 

 also a series of compound spots parallel with 

 the hind margin ; these are black, orange, and 

 white; and a sub-median white blotch be- 

 tween the middle of the wing and the hind- 

 marginal series of compound spots. 



Obs. I regret the necessity of acknow- 

 ledging my inability to differentiate perspicu- 

 ously the females of Adonis and Corydon. 



LIFE HISTORY. The CATERPILLAR rests in 

 a flat position on its food-plant, with the 

 ventral surface appressed to the leaves, and 

 its head, legs, and claspers concealed : if 



annoyed it will fall to the ground, with 

 both extremities slightly incurved; but the 

 anterior extremity most so; the head is 

 almost globular, but rather produced to- 

 wards the mouth; it is about one-third as 

 wide aa the second segment, and entirely 

 retractile within that segment; the body 

 is woodlouse - shaped, and in crawling, as 

 in resting, both the head and legs are con- 

 cealed ; the divisions of the segments are 

 decidedly marked : on the back is a double 

 dorsal row of eight approximate humps, two 

 on each segment from the third to the tenth, 

 both inclusive; the margin of the body is 

 dilated all round, and this greatly contributes 

 to the woodlouse appearance of the cater- 

 pillar ; the surface of the body Is finely 

 shagreened, and sprinkled over with black 

 dots, each of which emits a hort but rigid 

 bristle ; the surface of the caterpillar in this 

 respect closely resembles the glandular sur- 

 face of the stems and leaves of some plants : 

 these gland -like bristlea are particularly 

 observable on the dilated lateral margin: the 

 legs and claspert form a double medio-ventral 

 aeries. The colour of the head is dark brown, 

 almost black, and highly glabrous ; the body 

 is dull opaque green, with six longitudinal 

 series of oblong gamboge-yellow spots; two of 

 these series are dorsal and approximate, and 

 each series consists of eight such spots ; the 

 direction of the spots is rather oblique, and 

 the anterior extremity of each is rather nar- 

 rowed; these dorsal spots occupy the summits 

 of the humps already described ; another 

 series of very similar yellow spots is marginal, 

 occupying the lateral dilatation of each seg- 

 ment, and above this marginal series of yellow 

 spots are the circular and rather conspicuous 

 spiracles; in the two remaining series the 

 yellow markings are linear and ventral, and 

 equidistant between the claspers and dilated 

 margin. It feeds on various papilionaceous 

 plants, as bird's-foot trefoil (Lotus cornicu- 

 latus), kidney vetch (Anthyllis vulneraria), and 

 trefoil (Trifolium). On or about the 13th of 

 June these caterpillars changed to chrysalids, 

 at the bottom of the glass wherein they were 

 confined, without attaching themselves in the 



