65 



the upper surface, while those of the right, which are slightly detached from the body, 



^>S- **■ show the under surface. The two sur- 



faces differ but very little in colour and 

 markings. It appears on the wing a 

 little later in the summer than archipjnis, 

 and deposits it,s eggs on the willow, which 

 is its favourite fuod plant. Mr. Kiley 

 says that it feeds on the poplar and also 

 on the plum. Although the dUippm 

 butterfly resembles the iirchippus so 

 closely in the winged state, in the earlier 

 periods of its history it is very dis- 

 similar. 



The egg is well represented by Fig. 

 Colours, Orange, Red, Black and 'WTiite. 45^ and is a Very beautiful and interest- 



ing object : a shows it highly magnified, while at r it is s( own of natural size and in its na- 

 tural position on the willuw leaf. At d is 

 represented one of the minute cells of the 

 egg, very highly magnified, showing the lit- 

 tle threadlike processes which proceed from 

 each angle. Mr. Riley, who was the first 

 to ob.'erve this egg, thus describes it in his 

 " Third Annual lleport," page 154. Length 

 038 inch. Diameter at base about the 

 same. Globular, with top often slightly 

 depressed Hexagonally reticulate, the cells 

 more or less regul-ir, sunken so as to give 

 the egg a thimble-likc pitted appearance, and about ten of them in the longitudinal 

 row, and thirty in the circumfLrence. Covered with translucent filamentouss pines, one 

 arisins from every reticulate angle and giving the egg a pubescent apjrearance. Each spine 

 about as long as the cell is wide, those on the top being longest." He also says that the 

 colour of the egg is at first palo yellow, but it soon becomes grey as the young larva within 

 develops. These eggs are usually deposited singly near the tip of the leaf, generally on the 

 underside, but sometimes on the upper side, and occasionally two or even three together. 



The newly-hatched larva is nearly one tenth of an inch long, with a large yellowish brown 

 head. The body is pale yellowish brown with darker streaks, and with a few pale dots : nd warts, 

 from which latter arise pale spines or bristles. In abuut a mouth from the time of hatching 

 the larva becomes full grown, and appears as shown at a, Fig. 46, the following description 



Fig. 4G. 



of the mature larva was published by us 

 in the Can. Entomologist, vol. I, p. 94. 

 Found feeding on willow, July 24th. 

 Length one inch and a ()uarter. Head 

 rather large, flattened in front, strongly 

 bi-K.bcd, pale green, with two dull while 

 lines down the front, and roughened with 

 a number of small <rrcen and greenish- 

 white tubercles. Each lobe is tipped with 

 a green tubercle, or short horn. 



The body above is dark rich green, 

 with patches and streaks of dull white ; 

 the second segment is smaller than the 

 head, and its surface covered with many 

 whiti>h tubercles : the third segment dull 

 whitish crcen, raised considerably above the second, wiih a fl it ridge above, having a long 

 brnwnish horn on each side of il, thickly covered with very short white and brown spines; 

 fourth pcment sbout the same as third, with the same kind of ridge above, with a sm;ill tu- 

 bercle on each side, tipped with a bunch of short whitish .-"pines ; between the ridgcd on 

 third and fourth segments are two small black dots above. Each segment from fifth to thir- 



