NOTODONTIDjE. 159 



triangular spots or arrow-heads pointing inward between the 

 nervures ; cilia white, very short. Hind wings pale grey, 

 with the costal margin grey-brown ; nervures dark brown ; 

 a large cloudy grey central lunule; and the hind margin 

 spotted with dark brown ; cilia white. AntennaB of the 

 female threadlike ; body stouter, less downy, fore wings 

 usually more suflEused with black ; otherwise similar. 



Underside of the fore wings dark reddish-grey, or smoky- 

 grey to the second line ; beyond this, whitish with dark grey 

 clouds ; central spot blackish ; hind margin spotted with 

 black. Hind wings whitish with dark grey nervures, the 

 central spot large, ovate, black ; marginal spots rather large 

 and black ; body dark golden brown densely covered with 

 fur-like scales ; legs grey with the large tufts brownish. 



Variation is in intensity of dark colouring and extent of 

 black clouding around the markings ; and also, to some extent, 

 in ground colour, from warm reddish-white to pale dull greyish- 

 white. Dr. F. D. Wheeler states that larvee fed up from the 

 6gg upon apple leaves in confinement are devoid of the rich 

 reddish tinge which is so frequently seen in captured speci- 

 mens. This almost seems to indicate an effect of colour 

 produced by food, since the same result is certainly not 

 ordinarily obtained by the use of other food-plants. 



On the wing at the end of March and in April. 



Larva. — Head rounded, rather small ; body plump, with the 

 incisions strongly marked ; cylindrical, except that the twelfth 

 segment is raised into a blunt ridge or hump ; behind this 

 the thirteenth tapers off in a long curved slope ; legs and 

 prolegs stout and well developed, but much spread abroad, 

 the anterior and posterior extremities both raised and thrown 

 back toward each other in repose until the head almost 

 touches the dorsal hump. Head pale bluish-green; body 

 delicate green, whiter on' the back, bright yellowish-green on 

 the sides and beneath ; the usual dots slightly prominent and 

 large, pale yellow ; spiracles white edged with black ; on 



