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tuied, and the variation was of the same character as that of 

 the Erebia CEthiops, Esp., recently exhibited by Mr. Adkin. 

 A long discussion ensued. Mr, Barrett observed that this 

 kind of variation was almost confined to the Satyridse, only 

 a few examples in other families being known. Mr, Tutt 

 remarked that Weismann's theory of " histolysis " would aid 

 greatly in elucidating the causes of these variations. The 

 general idea had been that external influences must affect the 

 pupa as a whole, whereas, in reality, it might suffer only in 

 part. During the metamorphoses from larva to imago the 

 tissue was wholly broken down and rebuilt again in the pupa 

 stage, any excess such as would ordinarily exist going to 

 form pigment. If no excess existed, then the pigment would 

 not be normally developed. He explained how, in his opinion, 

 undue pressure might influence the coloration; of course damp 

 also might affect the pigment as well as retard development. 

 Mr. Barrett noted that all the Satyridae pupae were laid 

 close to the ground among the grass, and hence one side 

 would, no doubt, often be more exposed to damp than the 

 other. Mr. Step thought that pressure would tend to pro- 

 duce misshapen, crippled imagines, and Mr. Fenn said that a 

 considerable percentage of bred insects differed more or less 

 from the normal type in shape of wing. Mr. Tutt said that 

 when a larva suffered an injury the tissue was weakened, and 

 this weakened portion would not regain its vigour, but still 

 be weak when broken down in the pupa stage. Of course, if 

 the larva suffered from a deficiency of nutrition, the pupa and 

 imago would be affected as a whole. 



Mr. Tutt exhibited a series of Einydia cribrum, L., var. 

 Candida, Cyr., from the Alps, with New Forest forms for 

 comparison. The Alpine specimens were almost entirely 

 white, having scarcely a trace of the dark markings seen in our 

 British race of this species. The spot where they were taken 

 was very rocky, just below the larch region. The ground 

 was covered with dried and dead twigs of barberry and 

 juniper, to the white stems of which they were clinging. 

 He understood that in the Pyrenees there existed an abso- 

 lutely black form. Thus our New Forest form was an 

 intermediate, and the species was a very good instance of 

 variation by natural selection according to environment. He 

 also exhibited two specimens of the new British species 

 Cataplectica farreni, Wals., from Cambridge. 



Mr. Mansbridge exhibited the dry carcase of a mole taken 

 from a barn-door, which was covered with the dry frass, 

 cocoons, and pupa cases of a species of lepidopterous insect. 



