180 ORANGE SWIFT. 



pure satiny white, having all the wings margined 

 with yellow ; hut the female is entirely of the latter 

 colour, with various spots and streaks of deep hrown 

 on the anterior wings. The female is much less 

 frequently ohserved on the wing than the opposite 

 sex, and when the latter has discovered the place 

 of her retreat, he hovers over it with a peculiar 

 motion, not ohservahle in any other moth ; it is a 

 very irregular kind of flight, consisting of alternate 

 risings and fallings, accompanied with rapid zigzag 

 movements from side to side, confined to a space 

 not exceeding a few feet in circumference. This 

 singular vacillating motion, restricted for a while to a 

 limited spot, which it seems to haunt, together with 

 its snow-white vestments and time of appearance, 

 have no doubt been the cause of some fanciful ob- 

 server denominating this creature the " Ghost-moth/' 

 It is found in all parts of the country, the caterpillar 

 subsisting on the common Burdock, when its more 

 favourite food the Hop is not to be obtained. All 

 the species, when caterpillars, feed on the roots of. 

 plants. Previous to their change, they bury them- 

 selves in the ground, and construct an oval cell, the 

 walls of which are composed of particles of earth 

 ?md grains of sand, held together by an interlacement 

 of silken threads. The female moth lays a great 

 number of eggs, which are not for security aggluti- 

 nated to some stable object, as among the greater 

 number of Lepidoptera, but are ejected in rapid 

 succession from the oviduct with a kind of elastic 

 force which throws them to some distance. .They 



