55 



vbscuva, Tutt, although he could hardly reconcile the 

 description, leaden grey, with their very decided smoky 

 colour, which was of a brownish rather than a greyish 

 tone. 



Mr. Adkin also exhibited several insects on black pins, 

 which had been attacked by verdigris, and read the following 

 notes : 



" It is now upwards of a quarter of a century since black 

 pins were introduced. When first brought to our notice 

 there was a good deal of controversy as to their virtue as a 

 means of preventing the destruction of specimens by the 

 verdigris that was wont to accumulate upon the so-called 

 gilt and silvered pins that were in general use, the 

 advocates of the black pins asserting that they would 

 prove a panacea for all the evils that beset the collector of 

 Lepidoptera, while others with equal confidence predicted 

 that no benefits would be derived from them, and that the 

 natural grease of our specimens would soon soften the black 

 varnish, and that we should find ourselves in a worse plight 

 than before. On the whole I am inclined to think that from 

 the point of preservation of specimens there is some merit in 

 the black pin, but that it is not perfect in this respect is very 

 evident. The insects exhibited have all been pinned from 

 ten to fifteen years, and, with one exception where two are 

 affected, they are single individuals out of series of several 

 pinned at the same time, in which verdigris has made itself 

 manifest. But it will be noted that whereas in the case of 

 the gilt and silvered pins the verdigris usually accumulated 

 in considerable masses, often protruding for some distance 

 both above and below the body of the insect, the affected 

 specimens on the black pins usually show little, if any, 

 external signs of verdigris, the amount of it being small and 

 usually confined to a minute spot on the pin within the body 

 of the insect. The result, however, is equally disastrous, the 

 specimen becoming so contorted as to be quite useless, the 

 ultimate result usually being a complete bursting up of the 

 thorax. This appears to me to point to an imperfect cover- 

 ing of the pin with the varnish rather than to any softening 

 of the varnish by the insect's grease. It is only too often that 

 one finds pins stuck together, and it is almost a certainty 

 that many that have adhered to one another become sepa- 

 rated without being noticed. On being separated minute 

 portions of the varnish would chip off, leaving the metal of 

 the pin exposed, and it appears to me very probable that 

 from this almost unnoticeable imperfection in the varnish all 



