156 THE ZOOLOGIST. 



D.Jlliformis thallus. The paper, which was listened to with great interest, 

 was criticized by Dr. D. N. Scott, Mr. George Murray, and others. 



On behalf of Mr. D. J. Scourfield, a paper was communicated by 

 Prof. Miall on " Entomastraca and the surface-film of water." Briefly sum- 

 marised, the principal views advanced in this paper were the following : — 

 (1). To many Entomostraca, the surface-film of water is a very dangerous 

 element in their environment. To this category belong large numbers 

 of the Cladocera and Ostracoda. (2). To some others, on the other hand, 

 the surface-film affords peculiar advantages. This class includes, so far as 

 yet known, only a few specially modified Cladocera and Ostracoda, and 

 some Copepods, which do not, however, present any apparent structural 

 modifications. (3). In all cases (except where some Copepods possibly 

 make use of the properties of the surface-film to attach themselves to 

 aquatic plants above the general water-level) the relation to the surface-film, 

 whether beneficial or the reverse, depends fundamentally upon the same 

 physical principles, — namely, the upward pull of the surface-film when 

 forming a capillary depression, — and the possession by the animals of water- 

 repellent shells, ridges, scales, or setae, capable of penetrating the surface- 

 film, and producing capillary depressions. 



March 15th. — Prof. Stewart, President, in the chair. 



Mr. A. G. Tansley was admitted, and Messrs. J. H. Barkill and J. C. 

 Lisbon were elected Fellows, and Mr. Thomas Hick was elected an 

 Associate of the Society. 



Mr. Clement Reid exhibited some cones of Scotch fir, and also some 

 carbonised pine-wood from a peat-moss at Parkstone, Dorset. He said the 

 pine had become extinct in the South of England after Neolithic times, 

 and had been reintroduced only recently. Its extinction was commonly 

 supposed to be due to forest fires. He found that every piece of pine-wood 

 imbedded in the peat-moss was similarly charred, while portions imbedded 

 in sand were little altered, and he suggested that the appearance of burning 

 might possibly be due to the action of the growing peat, and have nothing 

 to do with fire. A discussion followed, in which Messrs. Carruthers, 

 Hanbury, Christy, and others gave reasons for adhering to the older theory. 



Mr. Carruthers exhibited a diagrammatic table, showing an accurate 

 counting of the annual rings of growth in three gigantic specimens of 

 Wellingtonia, Sequoia gigantea, from which he calculated the age of the 

 trees. A section of one in the British Museum (Natural History), 15 feet 

 in diameter, which was a living tree when cut down, he estimated to be 

 1330 years old. As illustrative of the size to which these trees grow, he 

 mentioned that he had measured two in America, one of which was 92 feet 

 aud the other 77 feet in circumference. A discussion followed on the 

 conditions which accelerated or retarded growth; and Mr. G. Murray, in 

 reply to a suggestion of Mr. Reid, pointed out that a number of experiments 



