96 



even some portion of blue sky. In the present case the 

 background of sky was intensely dark and practically 

 unicolorous, so that the conditions were unusually favorable, 

 and the brightness of the sky inside as compared with the 

 darkness outside the bow is well shown. In popular 

 accounts of the rainbow this is never mentioned, and the 

 explanation is only to be found in the encyclopaedias and 

 the larger treatises on light. 



"A curious circumstance is that when the photograph is 

 viewed upside down the contrast of tints appears much 

 stronger." 



Mr. Winkworth exhibited his extensive collection of Helix 

 virgata, showing the extreme variation obtainable in all the 

 characters of the shell, it being almost an impossibility 

 to meet with specimens which were identical in all par- 

 ticulars. 



Mr. Cuzner exhibited a number of microscopic slides of 

 Mycetozoa. 



Dr. Chapman exhibited a few Lepidoptera collected in the 

 Pyrenees this summer, including Lycama orbitulus, var. 

 oberthuri, L. pyrenaica, Anthrocera anthyllidis, A. contaminei, 

 Erebia lappona, var. sthennyo, E. lefebvrci, E. gov gone, E. stygne, 

 E. ceme, E. ccecilia, E. tyndarus, var. dromus, Oreopsyche 

 pyrenceella, Apterona pusilla, and Marasmarcha tuttodactyla. 



Mr. Robert Adkin exhibited specimens of Tortrix pronubana, 

 reared in June last from larvae collected in spring ; others 

 which emerged in autumn from larvae collected in Septem- 

 ber ; also autumn specimens which were reared from ova 

 deposited by the June moths, thus clearly demonstrating 

 that the species is double-brooded in this country. He 

 called attention to the variation in the orange colour of the 

 hind-wings in both sexes, caused, in the case of the darker 

 examples, by a suffusion of black or brown scales. 



A variety of Melanippe fluctuata, taken at Lewisham in 

 July last, in which the usual dark central band was repre- 

 sented by a mere speck on the costa and a slight enlarge- 

 ment of the discoidal spot. 



A series of females of Lyccena corydon, taken at East- 

 bourne in September last, showing more or less blue scaling, 

 chiefly in the hind-wings, but in two or three of them the 

 blue colour was well defined in the fore-wings also. 



Examples of a dark suffused form of Boarmia roboraria 

 from North Hampshire. 



Varieties of Abraxas grossulariata, in which the black 

 markings were in one case normal, in another excessive, and 



