PIERINAE: ANTIIOCHARIS GENUTIA. 1153 



Flight and postures of the butterfly. — Edwards says "it flics low, 

 swiftly, with a peculiar tremulous motion." This is true as compared with 

 tiie species of Pieris but hardly, so far as swiftness goes, in comparison 

 with Pontia. As observed by me at New Britain, I noted that it flies in 

 ratlier a leisurely fashion, two or three feet from the ground, with a gently 

 fluttering motion and in rather a zigzag course, which is intensified when it 

 is alarmed. It is not ditticult to capture even in the thickets if it is ap- 

 proached cautiously, but if any haste is shown on the part of the pursuer, 

 he will find the butterfly careful to increase the distance between them. 

 It appears to be always on the move, and I do not recall seeing it visit a 

 single flower in the two days that I saw it in company with Mr. Hulbert. 



When at rest the wings are held erect, those of opposite pairs not touch- 

 ing, the costal edges of the fore wings at right angles to the axis of the 

 body, the antennae spread at an angle of about 80°. On a side view the 

 latter are seen to be slightly arcuate, the apical half about parallel to the 

 axis of the body, the club scarcely curved upward and outward. At 

 more complete rest the wings are brought together and the fore wings sunk 

 behind the hind wings so that the costal edges meet. When walking about, 

 the wings are half opened (the planes at about right angles) and the an- 

 tennae are then more widely divaricate, say 90°— 100°. 



Desiderata. Although the natural history of this butterfly appears to 

 be of the very simplest nature, it has only been known within a year or two ; 

 and now there is less than usual that is obscure. It is hardly probable, 

 however, that we have exhausted the list of food plants of a caterpillar 

 so widely distributed, no parasites whatever are known in any stage and it 

 is altogether probable that a careful study of the out-door life of the cater- 

 pillar would reveal some interesting habits. We need many more details 

 concerning the geographical distribution of the butterfly. 



LIST OF ILLUSTRATIONS.— ANTHOCHARIS GENUTIA. 



General. Imago. 

 PI. 26, lig. 3. Distribution in North America. PI. 15, fig. 13. Male, both surfaces. 



Egg. 15. Female, upper surface. 



PI. 65, fig. 29. Plain. 35 : 14. Male abdominal appendages. 



Caterpillar, 40:5. Neuration. 



PI. 73, tig. 9. Caterpillar at birth. 46 : 41 . Androconium. 



76:5. Full grown caterpillar. 56:7. Side view with head and appen- 



79 : 54. Head, fifth stage. dages enlarged, and details of the structure of 



Chrysalis. . the legs. 

 PI. 84, fig. 59. Side view. 



»4S 



