152 THE MOTHS OF THE BRITISH ISLES. 



of the latter sex are quite as pale as any female. Figures 7 and 

 8 represent var. zatwta, Cramer. Originally this form was only 

 known to occur in Heligoland. The same, form, or a modifica- 

 tion of it, was described by Haworth as radiata^ from a York- 

 shire specimen. Then, in 1837, specimens of the variety were 

 reared with the normal form of the species from caterpillars 

 obtained at Saltfleet in Lincolnshire ; and subsequently a few 

 more examples were reported from the last named county, and 

 elsewhere. In 1891 a specimen of var. zatima emerged from an 

 assortment of chrysalids sent to Mr. Harrison of Barnsley from 

 a London correspondent. This particular specimen was of the 

 female sex, and it paired with a male which was also an 

 aberration, but not of the zathna form. Some of the offspring 

 resulting from this union were of the female parent form, others 

 favoured the male parent, and others again were intermediate. 

 In the course of a few generations almost entire broods of the 

 zathna variety were obtained. Allowing the sexes of zathna 

 to mate with those of more or less ordinary hibricipeda, the late 

 Mr. W. H. Tugwell obtained many very interesting aberrations, 

 one of which he named var. eboraci, and ^ixioih^r faschita. The 

 zathna form and its various modifications have now been reared 

 by entomologists all over the country, and presumably directly 

 or indirectly from the original Barnsley stock. In Yorkshire 

 especially the race has been improved ; the specimens are 

 larger and darker, and there is a tendency towards the almost 

 entirely black form known as var. deschangci. 



The pale whitish green eggs are laid in batches on leaves, 

 sometimes high up on birch trees, or Virginia creeper, but 

 more usually on the foliage of low growing plants ; it is often 

 common in gardens. At first the caterpillar is tinged with 

 yellowish, but it afterwards becomes greyish, and finally 

 brownish. When full grown the hairs, with which the body 

 is clothed, are brown ; there is a yellowish or whitish grey 

 stripe along each side, and an obscure somewhat reddish 



