53 



afforded them necessary protection. This led me to look higher up on 

 the house fronts; but although one may be gifted with fairly long sight, 

 to say whether the darkening of the compo some fifty feet or more 

 from the ground on which one stood was caused by the growth of 

 lichen, was too much of an undertaking. But it so happened that 

 in the house where I was staying I occupied a bedroom on the 

 second floor, and as the lower rooms had bay-windows, which my 

 room had not, I was enabled to get out of my window on to the roof 

 of the bay and examine the coping, which, although out of reach, 

 was not many feet above my head. Here I found not only a con- 

 siderable growth of lichen, but was also fortunate in detecting a 

 perfect insect resting close by it. Here, then, was the solution of 

 the problem, and it is interesting to know that although the species 

 may be exterminated from its lower feeding grounds, it is unlikely that 

 anything short of pulling down the whole of the houses on the sea 

 front of the town simultaneously would materially affect its numbers. 

 The specimens exhibited include a bred series and one of captured 

 examples ; each, it will be noticed, vary considerably both in colour 

 and the intensity of their markings. The former includes some 

 miniature specimens bred from the small pups before mentioned, 

 one of which is exceptionally dark and devoid of green coloration, 

 being simply a grey and black insect ; but none in the bred series 

 are of the pale buff colour that some of the captured examples are, 

 and I am inclined to think that this form, which is frequent among 

 captured specimens, is the result of fading. B. perla is a decidedly 

 commoner species in the district than the last-named, and may be 

 found on almost any old wall in the town, though more abundant on 

 the sea front than further inland. It appears to run into a local 

 form, having an appreciable amount of buff tone in the pale ground 

 colour. The series exhibited included the lightest coloured specimens 

 taken this year, and the majority of them show a decided buff tone 

 when compared with a series taken at Poole, in Dorset, last year, 

 which I have placed beside them for comparison. 



Another species that has interested me very much in previous years 

 is Acidalia marginipunctata, and it is needless to say that a sharp 

 look-out was kept for it ; but, being some couple of weeks earlier in 

 the season than I had been in recent years when I had found the 

 species, 1 hardly expected to meet with it. My wanderings in quest 

 of it were, however, not altogether fruitless, as on July 27th I met 

 with an unusually large, much-wasted example, sitting on the stones as 

 usual, a monument of an early brood, which had evidently passed, 

 and of which I had never previously been fortunate enough to find 

 even a trace. The only other example seen was on August 2nd. 

 This was resting just out of reach, and an attempt, after having a 

 good look at it, to get it under a pill-box simply disturbed it, and it 

 was lost. It, however, had the glossy appearance of a specimen just 

 fresh from pupa, and, I have little doubt, was an early example of the 

 later brood (see "Proc," 1896, p. 108). 



