NOTKS ON AGROTM ASHWOllTHU. 18.') 



affected by the locality in which it is found, the Denbighshire 

 specimens being both smaller and lighter in colour than those 

 found on the Silurian, the latter having the dusky cloud in the 

 centre of the wing nearly black, and the other markings clearly 

 defined, while the former generally have all the markings some- 

 what indistinct. If such slight changes in locality and climate 

 are enough to bring about these distinct differences, I think it 

 is not impossible that much greater changes may in time have 

 brought about correspondingly greater differences and modifica- 

 tions, until our present form has been the result. 



In Wales the moth was first discovered near Llangollen by 

 Mr. Ashworth, from whom it received its specific name ; after 

 his death the locality was lost, but was rediscovered about 

 twenty-five yea;rs ago, and since then the insect has turned up 

 in one two other places in the neighbourhood. 



The moth seems to occur pretty freely in its chosen haunts, 

 but owing to its nocturnal habits, and the character of its 

 habitats, it is difficult to obtain by night, and this, together 

 with the tedious work required to find it in the day time, will 

 account for its comparative scarcity in collections. I had the 

 good fortune last year to come across the locality at Penmaen- 

 mawr where it occurs, and thus had an opportunity of seeing 

 something of its habits. Through the day it sits on the face 

 of the cliffs, but its colour harmonizes so exactly with the rock, 

 and it conceals itself so carefully in cracks and angles, that 

 searching for it is a very tedious job. I spent the greater part 

 of ten days in this occupation and only succeeded in taking 

 eight specimens, but at the same time found several batches of 

 ,ova. These are laid in nearly every case. on the bare rock, in 

 .batches of thirty or forty, very often nowhere near any plant on 

 •which the young larvae could feed on emergence, and unless 

 ..they are gifted with great fasting powers I think many must 

 die before finding the necessary food. The eggs hatch during 

 the last fortnight of July, and the larvae feed slowly on golden 

 rod, various grasses, or thyme for about six weeks, at which 

 period they are about half their full size. In this stage they 

 proceed to stow themselves snugly away in holes and corners. 



