THE MOTHER OF PEARL. 495 



diction, the older name is by common consent abandoned, and 

 the next in seniority takes its place. There are, of course, 

 some disadvantages in this system, but they are enormously over- 

 borne by its advantages, for, without some such system, there 

 would be no fixed nomenclature of insects, and every one who 

 thought that he could improve upon a name would do so, and 

 the result would be an inextricable confusion, which every 

 year would augment. 



In the genus Botys, the body is larger than the wings, and 

 both pairs are marked in a similar manner. 



The colour of this pretty little Moth is pearly-white, on 

 which are a number of dark markings arranged as shown in the 

 illustration on Woodcut LVII. Fig. 2. The popular name of 

 this insect is the Motifeii of Pearl, and its scientific name is 

 Botys urticalis. 



Although the general character of these marks is the same 

 in all species, there is some variation in difierent specimens, 

 both in their arrangement and depth of tint. In colour they 

 are nearly black, but if viewed by a side light, a purjjlish 

 metallic gloss is seen upon them, being best defined along the 

 costal margin of the upper wings. Both surfaces are coloured 

 in much the same manner, but on the under surface the marks 

 are not so dark, and the purple gloss is more conspicuous, 

 especially on the lower wings. When closed, the wings assume 

 a heart-like shape, and usually look very round, as if a flat 

 plate of thin mother of pearl had been cut into the shape of a 

 heart, and carefully painted with dark spots. The thorax is 

 bright golden-yellow, the abdomen is black, each segment being 

 edged with yellow, and there is a tuft of yellow hairs at the end 

 of the tail. 



The caterpillar is one of the numerous nettle-feeders. It is 

 thicker in the middle than at the ends, and so thin-skinned 

 that it has a semi-transparent appearance when viewed against 

 the light. Its colour is whitish-grey on the back, relieved by 

 a central black line, and the sides are green. This larva is 

 shown at Fig. a on Woodcut LVII. It draws together the 

 leaves of the nettle with silken threads, and so feeds in conceal- 

 ment. There are ten species of this pretty genus. 



On Woodcut LVII. Fig. 3, is seen the Moth which is po- 

 pularly called tlie Lesser Pearl (^Spiludes cinctalis). 



