ABSTRACTS OF LECTURES. 6 1 



ABSTEACTS OF LECTUEES 



DELIVERED AT THE EVENING MEETINGS OF THE 

 SOCIETY, WINTER SESSION 1902-1903. 



November nth. — The Life and Death of Trees. 



By Prof. M. C. Potter, M.A., F.L.S. 



In this lecture the growth of a tree stem was first traced 

 step by step from its emergence from the seed up to the 

 condition found in the fully formed timber. The formation 

 and coalescence of the vascular bundles, the way in which 

 the successive rings of woody tissue are added, the arising of 

 branches, and other points in the economy of the tree were 

 described and illustrated with the help of diagrams and 

 photographs shown with the lantern. The second part of the 

 lecture was devoted to exhibiting some of the ways in which 

 the life of the tree is brought to an end, with reference more 

 especially to the different types of fungoid growths which 

 often play such an important and destructive part in the 

 process. The struggle that takes place between the tree on 

 the one hand trying to heal over its wound, and the fungus 

 on the other forcing its fibres more widely and deeply into 

 the substance of the wood, was brought strikingly before the 

 audience in a series of photographs of trees attacked by 

 various of these parasites. Many of the photographs were 

 taken in the neighbourhood of Newcastle. 



December i6th. — Deep Sea Life. 



By E. p. Witten, B.Sc. 



The last century has witnessed remarkable advancement 

 in the progress of natural research and in our grasp of 

 biological problems, but in no branch so much as in marine ; 

 zoology. Little over a generation ago, though forms inhabiting 

 the coast regions had been carefully observed, the deeper 



