44 



the emerging the wings were of full size. There was, therefore, no re- 

 plenishing of waste nor reparation of parts in the scales of lepidoptera, 

 as in the hairs of the mammaha. 



Nor could we trace in all scales the cuticular layer, cortical sub- 

 stance, and medullary substance of such hairs ; we seemed to obtain 

 a cortical substance, with or without a cuticular layer, and sundry rib- 

 like strengtheners, which had given rise to the diversity of opinion as 

 regarded structural markings. There was another curious fact some- 

 times noticed— viz., that there appeared to be a power on the part of 

 the insect to raise the rows of the scales as well as to inflate some 

 scales. He had often found the scales on the wing of a butterfly 

 caught and killed in flight, not lying flat to the wing membrane, but 

 raised on it at a more or less acute angle, as though in flight the insect 

 possessed the power of raising the rows of scales. This might, if we 

 imagined the power of inflation of the scales as well, give greater 

 buoyancy to a butterfly or moth in flight. He had every reason to 

 beUeve this to be true of some scales ; if so, it would give to the wing 

 membrane with its nervures a power not accorded to it in Manuals on 

 Entomology. 



It was now twelve years ago he started one afternoon with a 

 medical friend to look for a certain fern, said to grow about twelve 

 miles from Brighton. They got out of a train at the Hassock's Gate 

 Station, and diverged a little from their course to see whether Neottia 

 Spiralis (autumn lady's tresses), the orchis which Darwin watched the 

 bees fertilizing, by carrying tha pollen masses from one flower to 

 another, was in flower. While searching for this plant, some blue 

 butterflies got up. His friend and he managed to catch several. This 

 fact was strongly impressed on his mind, because, after walking nearly 

 a mile, they retraced their steps to search for a stethoscope, which, in 

 the eagerness of the chase, had dropped from his friend's hat when 

 catching a " blue ." 



On the way they both talked over the question of why they had 

 not been able to find " battledore " scales on blue butterflies. Was it 

 they were only on one kind, for though they had both searched for 

 them on the part described in the Micrographic Dictionary, p. 564, 

 under Polyommatus, they had neither been able to find them. The 

 words there run, " The scales upon the under surface of the wings of 



