THE SWALLOW-TAILS. 



margin (Plate XXXVI shows the male); below, the 

 front margin, at least, of the green cloud is replaced by a 

 row of orange spots. The larva feeds chiefly on sassafras 

 and spice-bush (Benzoin) ; it makes a series of successively 

 larger shelters for its resting times by folding a leaf at the 

 midrib, fastening the fold by silk threads placed near the 

 crease instead of at the edges. It keeps these shelters 

 scrupulously clean, eating its cast skin, when it molts, 

 except that it throws out the inedible cast "skull." 



A sometimes-used scientific name, asterias, 



Pa , pilio is also the common name. Plate XXXVI 



polyxenes 



shows the female; the male is not so dark, 



his blue spots are not so pronounced, but his yellow spots 

 on the inner row are much larger. The larva is wasteful; 

 it eats our parsley and carrots, instead of sticking to 

 umbelliferous weeds, and does not eat its cast skins as do 

 its near relatives; otherwise it is a beautiful creature 

 which, like many of its relatives, changes the color and 

 cut of its dress at every molt, and which will stick out 

 its orange horns if you but threaten to poke it. The 

 species is found throughout the Atlantic States and the 

 Mississippi Valley; what have been considered races of it 

 extend this distribution to most parts of North America 

 and south to Cuba and Peru. 



Plate XXXVI shows the male Pipe-vine 



api 10 Swallow-tail ; the female has a row of 



philenor . 



distinct spots on each fore wing, correspond- 

 ing to those on the hind wings. The inner margins of 

 the male's hind wings are folded over and contain scales 

 which give off a faint odor, presumably for the sake of 

 pleasing the female. It should be said that many male 

 Lepidoptera have similar scent-scales, placed in various 

 parts of the wings, body, and legs. The larva of philenor 

 feeds on the Dutchman's-pipe (Aristolochia] and differs 

 from most of its relatives by having, even when mature, 

 fleshy spines on several of the front and rear segments. 

 Instead of depositing her eggs singly, the female lays them 

 in little bunches; and the larva?, when young, feed side 

 by side at the edge of a leaf. 



141 



