314 THE MOTHS OF THE BRITISH ISLES. 



A photograph, by Mr. H. Main, of the caterpillar, is repro- 

 duced on Plate 138, Fig. 3. The general colour is grey, 

 inclining to yellowish or brownish ; sometimes it is reddish 

 brown ; two broken dark-grey lines on the back, and some pale 

 blotches on the sides. The caterpillars of the first race 

 {bistortatd) feed in May and June, and again in August and 

 September. Those of the second race in June and July, or 

 later. They seem to eat the foliage of trees, including those in 

 orchards. 



Note. — Cross-pairings between bistortata ^ and crepuscu- 

 laria $ resulted in the ab. ridingi, Tutt, whilst the offspring of 

 a crossing of crepuscularia q and bistortata $ have been named 

 bacoti, Tutt. Pairings of bistortata $ and delamerensis ? 

 produce ab. ridingi-suffusa, Tutt ; and those of delamerefisis ^ 

 and bistortata 9 = bacoti-suffusa, Tutt. Further, bacoti-suffiisa 

 will pair with ridi?igi-s7iffusa, or the last named with crepuscu- 

 laria; the progeny being in the first case mixta^ Tutt, and 

 in the latter, reversa, Tutt. 



Brindled White-spot {Tephrosia hiridatd). 



Two examples of this species (also known as extersaria^ 

 Hiibner) are depicted on Plate 137, Figs. 16,2 9 . There is 

 variation in the amount of black speckling and in the strength 

 of the cross lines. 



The caterpillar is dull hazel or chocolate brown, often tinged 

 with green ; a row of whitish dots on each side of a series of 

 pale spots along the middle of the back ; rings 4 and 8 barred 

 with black-brown or dusky rust colour. Sometimes the general 

 colour is green. (Adapted from Fenn.) It feeds in July and 

 August, or even later, on oak and birch, sometimes on alder 

 and sallow. The moth is out in May and June, earlier or 

 later in some seasons. In Britain apparently confined to Eng- 

 land, where it occurs locally, in woods, from Worcestershire 



