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vided for from the earliest stages of the growth of the plant ; he did not, how- 

 ever, make use of the term " corky," nor did he speak of " cork cells," because 

 at that time it was not so generally known that the material was so nearly allied 

 to that of cork. The fall of the leaf was before their eyes constantly, and was 

 on that account likely to be little noticed ; it was, however, an occurrence of 

 great interest, and became increasingly so when it was found to be provided for 

 in the manner described, in the early growth of the plant, and when the arrest 

 of growth and the deposit of the cork cells was understood. He thought, how- 

 ever, that there were some other circumstances which had at least some slight 

 influence in contributing to the fall of the leaf. It was found that the ashes of 

 dead leaves contained more of the salts of lime and potash than the ashes of 

 living leaves j and if there was an increase in the deposit of solid constituents, 

 this would undoubtedly add to their brittleuess. He thought, also, that the 

 changeful nature of the climate in autumn must have considerable influence on 

 the mechanical relations of tissue, which had ceased from active growth. In 

 the tropics most of the trees were evergreens, but they cast their leaves at 

 intervals, and it was noticed that after a very dry season they threw them off 

 more frequently than was the case after wetter seasons, showing thus that 

 climate had much to do with the process. The corky substance was found also 

 in many other portions of plants — the cuticular layers, for instance, had it, and 

 it gave hardness to many other parts. He thought that Mr. Jackson had done 

 what was very meritorious in reading them this Paper, and he hoped the 

 example would be followed, and that other members would be induced to bring 

 forward translations of similar papers on common subjects -for although this 

 was a common subject, it was treated, as they had heard, in a very scientific 

 way. It did not show all that could be brought forward to explain the subject, 

 but it was a paper of much interest, and showed them an example of the 

 wisdom of God in making provision even in the early growth of the plant for 

 that which was to take place during its later existence. 



Mr. Thos. Spencer said that he happened to be present on the occasion when 

 his friend Dr. Inman read the paper which had been mentioned. It had ahrays 

 struck him since then, on thinking the matter over, that trees which secreted 

 resin did not show a general fall of the leaf. All that was stated in the paper 

 hardly explained this fact, which was noticed in the holly, fir, and laurel. He 

 thought that in those cases the varnish which was secreted prevented evapora- 

 tion from taking place. 



The President said that the evergreens shed their leaves as well as other kinds 

 of trees, though they did not do it quite by the same process. He did not think 

 that the resin had much to do with it. 



The Secretary thought that analogous cases were to be found in the animal 

 kingdom, and instanced the shedding of the horns of the stag, in which circula- 

 tion, after going on for a long time, at length ceased in consequence of the 

 deposit of calcareous matter at the base of the antlers, and nutrition having 

 been thus arrested the antlers fell off as effete bodies. 



The President said that Mr. White was quite right in referring to this cir- 

 cumstance ; in fact, similar processes might be found going on throughout 

 creation. The fall of the leaf had, however, always been a topic of interest 

 and was a favourite simile with the poets in all ages, — the leaf being taken as a 

 type of human existence, — its early unfolding from the bud was aptly compared 

 to the opening character of childhood,— its beauty and its greenness to the 

 period of juvenescence, and so on to its fading and its fall as types of sere old 



