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forced its way through the earth, the pupa being destitute 

 of free segments which would enable it to work itself out. 



Mr. R. Adkin exhibited specimens of Vanessa iLrticce, L. 

 Three examples bred from larvse taken in Sutherlandshire. 

 In one the central, costal, and inner marginal blotches were 

 united. He also exhibited a wasp's nest found in a hogs- 

 head of tobacco from U.S.A., with the insect in situ. 



Mr. Carrington exhibited several specimens of flint from 

 Chatham, Kent, having dendritic crystals upon them. He 

 said that they were comparable with Mocha stones, which 

 were agates having a beautiful arborescent pattern in them. 

 The people of India were most skilful in cutting these stones 

 so as to show the patterns to advantage with only an exceed- 

 ingly thin film over them. This pattern was a deposit of 

 oxide of manganese, and the theory was that fissures had 

 become saturated with a fluid containing the oxide, which 

 when the fluid (most likely water) evaporated was deposited 

 in these beautiful arborescent patterns. Such crystals in 

 copper, taken from rock fissures, but of course very much 

 larger, were to be seen in the Geological Museum, Jermyn 

 Street. Many of the recently broken flints by the road side 

 had these patterns on them. It was best to varnish the 

 specimens to prevent the crystals being dissolved by moisture 

 or rubbed off. 



Mr. Tutt referred to a most interesting change in number 

 of spots within recent times in Zygcena trifolii, Esp. He 

 said that some fifteen years ago Mr. Ovenden and himself 

 used to take this species in two fields some distance apart. 

 In one field the species suddenly disappeared, and in the 

 other it gradually died out. They were of two distinct 

 forms, all small but genuine five-spotted Z. trifolii, yet 

 having amongst them one or two specimens with six spots. 

 They were always to be taken the first week in June, while 

 the true Z. filipendnlce never appeared until a month or six 

 weeks later. In i8gi the species suddenly appeared in 

 abundance in one of the fields at the beginning of June, but 

 strange to say only six or seven undoubted Z, trifolii were 

 among them. About thirty of those taken had an indistinct 

 sixth spot, while all the rest were to all appearances true 

 Z. filipendulce forms except in size. Reference was made to 

 Mr. W. H. B. Fletcher's experiments with the British 

 Zygsenidse, showing that the filipendtdce character would 

 assert itself in most of the broods. He also said that 

 Messrs. Boden and Richardson had reported cases of early 

 Z . filipendidce with a faint sixth spot. Mr. Briggs had early 



