277 



color, heart shaped above, and much larger than the second segment, beset 

 around the sides with little tubercles. This larva was very sluggish, ate very 

 little and grew slowly; on July G, it had grown to the length of one and one 

 fourth inches; the tubercles after the first moult (since its captivity) have 

 become elongated; the top of the second segment has become distinctly 

 pale or whitish, and the white patch on the back is larger; there is a 

 whitish, elongated triangle extending along the sides of the hinder extrem- 

 ity, from the hindmost feet to the side above the penultimate feet; there are 

 oblong tubercles or elevations in pairs on the top of the third, fifth, tenth 

 and eleventh segments. 



Pupa, July 8. Imago, July 20. 



Cynthia Cardui Linn. [PL i, figs, l, 2.] 



About the last of June and first of July, 1830, numerous larvae of various 

 sizes were observed on the Onopordon acantliium, on the Cnicus benedic- 

 tus (two kinds of thistle), and on the garden hollyhock. These larvas bore 

 a general resemblance to each other in form, etc., though varying much in 

 colors. Their habits were the same. They spin a thin web on the surface 

 of the leaf, which they draw over by means of the threads of silk which are. 

 attached to the edges, thus forming a kind of tent within which the larvae 

 feed on the upper surface and pai-enchyma of the leaf without touching the 

 tinder cuticle. When this is exhausted the larva leaves its tent and forms 

 another in the same way. Very small larvaa only cover themselves with a 

 portion of the leaves, and are principally protected by means of a silken 

 tent. The larvae live separately, but many are found on the same plant. 



July 5. Two full-grown larvae of the Cnicus suspended themselves by 

 the tail; their colors were so much changed as to be indistinct. These 

 larvae had fed equally well upon leaves of the Onopordon. A third pre- 

 pared to suspend itself at the same time. It was one inch and a half long. 

 The head piceous black, slightly indented above or heart shaped ; the 

 body of a dirty white color, ornamented above with small, deep black and 

 larger, confluent, yellow spots, the former running together so as to produce 

 a dorsal line, and the latter forming an interrupted lateral line, and two 

 similar but narrower dorsal lines upon each side of the black dorsal line. 

 A broad, blackish, lateral streak on the first four segments just between the 

 first and second series of lateral spines. Each segment with a transverse 

 series of spine-bearing tubercles. The tubercles of a pale reddish color, 

 the spines branched, white, tipped with blackish. Except on the first three 

 segments (where the dorsal spines and tubercles are wanting) there are 

 seven spines on each segment; one dorsal, and on each side two lateral, above 

 the stigma, and one below the stigma on the lateral yellow line. Below 



