BUTTERFLIES OF THE DISTRICT OF COLUMBIA 189 



Caterpillar. — The fully grown caterpillar is commonly known as 

 the " elephant worm." Just behind the rather small head the body 

 is much swollen, from this swollen portion tapering gradually to the 

 hinder end. The color is rich velvety green, becoming paler below. 

 The third segment behind the head bears two large and conspicuous 

 eye spots, while the following segment is bordered behind with 

 yellow and the next is edged in front with black. 



There is no other caterpillar with which this could possibly be 

 confused, except perhaps that of the spicebush swallowtail {Papilio 

 troilus). But the latter is darker in color and there is a pair of 

 black-edged bright patches just behind the eye spots. 



Just before changing to the chrysalis the caterpillar becomes on 

 the swollen anterior segments a dull dirty green, and posteriorly a 

 grizzly green. 



The caterpillar feeds on a very large variety of trees and bushes, 

 in this region living always high above the ground. It is to be 

 looked for especially on the tuliptree {Liriodendron) ^ ash, hoptree, 

 and on fruit trees. Farther south it sometimes does considerable 

 damage to shade and forest trees. 



Chrysalis. — The chrysalis has a rough and rugose surface, the 

 anterior half makes a straight line with the posterior half, and the 

 abdomen is not expanded laterally; by these characters it is easily 

 distinguished from the chrysalids of all our other swallowtails. In 

 color it is mottled brown, occasionally more or less extensively 

 marked with green. 



PAPILIO TROILUS TKOILUS Linnaeus 



Spicebush Swaixowtail 

 Plate 44, Figure 2 ; Plate 45, Figures 1, 2 ; Plate 46, Figures 1, 2 



There can, I think, be no doubt that the insect recorded by Warden 

 under the name of Papilio polydamos is in reality this species. His 

 specimens were damaged in transit, and it would be very easy to 

 mistake a damaged troilus for 'polydamas. 



Apparently Warden's determinations were made with the aid of 

 Drury's figures. Under the name troilus., Drury, through an error 

 in determination, figured the male and female of P. polyxenes^ and 

 the figure in Drury's work which is most like troilus is that of Papilio 

 polydamas [anfiquusi from Antigua. 



Occun^ence. — Common throughout the District and the surround- 

 ing country, in some seasons very conmion. Within the District it 

 is much less abundant than in former years, and its numbers seem 

 to be steadily decreasing. 



The spicebush swallowtail is a woodland species, and is less fre- 

 quently seen in fields and gardens than the yellow, parsnip, or blue 

 swallowtails. It is especially to be found in low damp woods, par- 



