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Mr. C. HASTINGS DENT, F.L.S. I think that papers like the present are 

 especially valuable as bringing forward some of the weak points of the theory 

 of evolution. Although I have not done more than look into fossil botany, 

 it is very closely allied with zoological studies, which have always had great 

 interest for me. There is one point to which I should like to refer, namely, 

 the sudden appearance of groups of families in the geological strata, which 

 appear to form a powerful argument against the doctrine of evolution. It is, 

 I think, particularly noteworthy when we find the representatives of the same 

 genera existing in a similar condition at the present day. Professor 

 Williamson, stated in Nature in the winter of 1881-2, that he 

 thought it doubtful whether it was possible to make clear the process by 

 which the evolution of phanerogams from cryptogams has been accomp ished. 

 Darwin, perhaps, would give two general types one for phanerogams and 

 one for cryptogams. Here we have two types separated by a vast amount of 

 time two separate creations ; and it may be asked, if there are two, why 

 not a hundred ? I would say a word as to the persistence of type, and 

 another with regard to the persistence of species. In reference to the per- 

 sistence of type, there is the small equisetum (E. sylvaticum) occurring con- 

 tiguous to or in the soil overlying the coal measures, and is found only in 

 such localities, flowering in June and July. It is plentiful in the neighbour- 

 hood of Manchester, where it maybe found growing in the cloughs and valleys 

 of the coal district. Then, as to the persistence of species, there is the Salix 

 herbacea, which I first found on the summit of Snowdon, and afterwards, on 

 a visit to the Lake District, upon the tops of Mount Skiddaw and Scawfell 

 Pike, though I failed to find it on Helvellyn. All these mountains are 

 something over three thousand feet in height. It occurs to me that this 

 plant is a survival from the glacial epoch, and that, as the]temperature of the 

 British Isles has increased, this little willow, which is the smallest known 

 species, and only attains a height of two or three inches, gradually found its 

 way from the increasingly warm low ground until it is now isolated on the 

 tops of the highest peaks. A reference is made on pages 11 and 12 of the 

 paper to the Falkland Islands, which is specially interesting, as it is very 

 likely a similar case to that which I have noticed with regard to the Salix 

 herbacea, the ranunculus form being found in the Falklands, whereas in the 

 Brazils no species of that genus have been discovered ; and I may mention 

 that, owing to the enormous preponderance of water in the southern hemi- 

 sphere, in the temperature of the latitudes there, 40 degrees south, represent 

 50 degrees north. There is one question I should like to ask Mr. James ; and 

 that is, what is his opinion as to the dispersion of plants, which he has not dealt 

 with in this paper ? I know it is a very difficult subject to enter upon, but it is 

 one which might have given rise to some interesting remarks by way of debate ; 

 whereas I venture to think that no one in this room, even if it had been five 

 times as full as it is now, could find a single subject of debate in this paper. 

 I should like to know his opinion on this matter, especially as we are not 

 required to hold so dogmatic a belief on the question of dispersion from a 



