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advantage in the struggle for life. It is probable that a re- 

 semblance between a parasite and its host would serve some 

 useful purpose to the former, and in time become characteristic of 

 the species. Specimens were shown of Kumex Acetosella round 

 which trailed the similar shaped leaves of Convolvulus Arvensis. 

 May not these be left untouched because of their likeness to 

 leaves with such distinctly acid properties as the sheep's sorrel ? 

 In an oak copse the author had noticed the leaves of the woodbine 

 so similar to those of the trees on which it climbed as to be 

 undistinguishable at a little distance. In a Sussex lane last 

 summer he was much struck with the extraordinary similarity of 

 some bramble leaves to those of the shrubs round which it grew. 

 Several examples were shown at the meeting. The cause of this 

 variability of foliage is often difficult to discover. It may be in 

 the environment of the plant. There were many interesting 

 problems connected still remaining to be solved. It is possible 

 that a particular leaf-shape engendered by growth, fostered by 

 circumstances, and strengthened by habit may result finally in 

 the evolution of new species. 



" The Succession of Life on the Earth, and its Possible 

 Migration from the Polar Regions." 

 Mr. Edward Crane, F.G.S. 

 Read March 9th, 1887. 

 The author, by the aid of a number of large diagrams, gave an 

 excellent resumi of the general course of life on the globe, and 

 remarked on the principal features of the different epochs. He 

 noticed particularly the gigantic crustaceans of the Lower Silurian 

 rocks, and the interesting problems connected with their evolu- 

 tionary history. The singular persistence of some genera of 

 Brachiopods through vast periods of time from the Cambrian age, 

 in fact, to our own, was touched on. The author also referred to 

 the recent extraordinary discovery of a highly developed scorpion 

 in the Upper Silurian of Sweden, and to the fact that the first 



