202 THE CANADIAN ENTOMOLOGIST. 



able caterpillar are of great interest to the student. In the north, includ- 

 ing the whole of Canada, the males and females are hke our figure, 

 having the ground colour of a pale lemon yellow, with rich black mark- 

 ings. The broad margin is more or less powdered with blue scales, 

 particularly on the hind wings, which are further ornamented with a 

 conspicuous orange-red spot, bordered with black and blue, near the 

 hind angle, and in the females there is another large spot of the same 

 colour at the upper angle. In the Southern States the specimens of both 

 sexes are larger and more highly coloured, and besides a black 

 dimorphic form of the female also occurs. No specimen of a black male 

 has ever been taken. The only approach to this melanic form is the 

 beautiful suffused variety which is figured below. The range of the 

 Tiger-Swallow-tail is very extended. I have some specimens from the 

 arctic circle and others from the tropics, while from east to west it 

 occurs from Newfoundland to Alaska. The eggs are laid by the 

 females singly on the upper side of the leaves of its food plants. They 

 are about one-twentieth of an inch in diameter, sub-globular and smooth, 

 at first of a pale transparent green, much yellower at the base by reason 

 of a more or less abundant waxy substance which fastened them to the 

 leaf; after a few days they turn reddish, and just before the young larvae 

 hatch they are almost black. The time of hatching varies with the 

 weather from ten to twenty days. The caterpillars are very different 

 in appearance during their various stages. In the first stage the general 

 appearance is black, with white spots and tubercles, and a conspicuous 

 white saddle-shaped mark on the back. This mark also appears after the 

 first and second moults, but is then of a pinkish cream colour. After the 

 second moult the ground colour of the body usually changes to greenish 

 brown. After the third moult the green colour is much more decided, 

 and the caterpillar assumes more of the shape and markings of the full- 

 fed larva. The thoracic segments are now enlarged and the saddle- 

 shaped mark is almost obliterated. There is a yellowish band in front of 

 segment 2, and another on the hinder edges of segments 5 and 12 ; that on 

 5 is followed closely by a black line on the front edge of segment 6. 

 This black line does not show when the caterpillar is at rest. The head 

 is pink brown. On each side of segment 4 now appears a pear-shaped 

 yellow eye-like spot, the larger end outwards. This spot is edged by a 

 fine black line ; inside there is a heavy black line enclosing a violet spot. 



