102 PLUSIA ORICHALCEA. 



having the underneath part and the wing-cases of a 

 lovely pale green, a colour which, three or four days 

 before the perfect insects emerge, gradually changes 

 into a dull pink, foreshadowing the colouring of the 

 under side of the abdomen and wings of the imago. 



The habit of the larva appears to be to eat the 

 young top leaves of the Eujpatorium, and work down- 

 wards. When not engaged in feeding it rests on the 

 under side of a leaf, grasping the midrib. 



One larva, in the course of its last moult, failed to 

 throw off its old skin in its entirety ; a narrow band 

 of which remained in an oblique position, embracing 

 the eighth segment, the hinder part of the seventh 

 segment on one side, and the former part of the ninth 

 on the other. This band, as it dried, had tightened, 

 constricting the body till it was only half its normal 

 diameter, and enabling the w r hole of the internal 

 structure and workings to be plainly seen. As the 

 larva was evidently unable to extricate itself I care- 

 fully inserted the eye of a needle beneath the ligature, 

 -and, aided by sundry energetic wrigglings of the larva 

 itself, split it asunder. The body soon resumed its 

 usual dimensions, and the larva fed up and turned all 

 right, and the imago emerged apparently perfect ; 

 but when I got it on the board I found the left fore- 

 wing, though not crippled, about one-eighth of an 

 inch shorter than the right. 



I think it is quite possible that Plusia orichalcea 

 may be more widely spread than is generally supposed. 

 The perfect insect is rarely seen except at night, 

 and the larva would be easily passed over as only 

 PL gamma. I hope to be able to give a fuller account 

 of its earlier stages another year. (W. Warren, 

 September 17th, 1883; E.M.M., October, 1883, XX, 

 116.) 



