124 



descend on themselves, as it were, and move fastest in the middle. 

 If they moved by alternate thawing and freezing, since these 

 processes occur most readily on the edges, the motion would be 

 greatest there, and they would be depressed below the centre. 

 He himself was inclined to the opinion of Mr. Desor, that gla- 

 ciers are in the condition of a soft solid substance, like a mass of 

 dough for instance, and descend principally by the force of 

 gravity. Such a mass descending in a confined space would 

 naturally take the bowed shape noticed in glaciers. He suggest- 

 ed that the laminated structure mentioned by Prof. Rogers, 

 might be caused by the freezing of water which had run down 

 the sides of the barrier mountains. 



Dr. Gould read a note from Prof. J. W. Webster of 

 Cambridge, presenting to the Society a number of medi- 

 cinal plants from the interior of Paraguay. The thanks of 

 the Society were voted for the donation. 



Mr. Bouve announced a donation from Mr. Theo. Lincoln 

 of Dennis ville, Me., of several impressions of Fucoides on 

 sandstone. The thanks of the Society vi^ere voted to Mr. 

 Lincoln. 



Prof. Rogers presented various books from Mr. Double- 

 day, The Entomological Society of London, Mr. Spence, 

 Mr. Tilton, and Mr. Adam White, for which see Quarterly 

 List. Prof. Rogers announced that sets of casts of the Fos- 

 sils in the British Museum had been made, and were to be 

 obtained at the Museum at cost, it being the object of the 

 Managers of the Institution to make its collection as exten- 

 sively useful as possible. 



