318 TllANSACTIONS AND rUOCEEDIXGS OF [Sess. lvi. 



secoud period is miieli more marked. Of eleven species, the 

 only one which prefers the first is Aca: In Car-pinus there 

 is almost an equilibrium. The extremes are — Acer, with 55, 

 45, and Liriodaidron, with 10, 90. 



Comparing the species which occur in both groups, a 

 remarkable agreement is found in Acer, 50, 44, and 55, 45 ; 

 in Fagus, 40, 60, and 38, G2 ; and in Qacrcus Ilohur, 35, 65, 

 and 38, 62. But there is a considerable difference in 

 Car-pinus,AQ, 60, and 51, 49 ; in Q. Cerris, 47, 53, and 31, 69 ; 

 and a very great contrast in Tilia, 67, 38, and 24, 76 ; and 

 Bctida, 50, 50, and 24, 76. 



On the whole, the proportions may be considered as well 

 made out in Acer, Quercus Eohur, and above all in Fagus, as 

 the observations rest on a considerable number of trees in 

 each case. Hardly less reliable, perhaps, in the younger group 

 are Tilia, Fraxinus, Ulmus, Betula, JEscidiis, and Poimlus 

 fasti/jiata, because, although only two trees of each were 

 measured, their proximity to each other in the list of fifty- 

 eight inspires confidence in the reliability of the average 

 deduced ; and this notwithstanding the wide divergence of 

 the single trees of the older group in the case of Tilia and 

 Betula, which may l)e due to some abnormality produced 

 by their slow growth. 



The only thoroughly established additional species from 

 the older group is Q. conferta, although the close agreement 

 of the two specimens of Q. Cerris suggest reliability, not- 

 withstanding the wide divergence of the single specimen in 

 the younger group. 



The remaining eleven species are more doubtful — Car- 

 pinus, Prunus, Pyrus of the younger group, — because of the 

 wide divergence of the results in the two specimens of each; the 

 others, because only one tree of each was measured, although 

 there can scarcely be a doubt that the proportions in Lirioden- 

 dron are substantially correct, its small proportion of 10 p.c. in 

 the first period being fully accounted for by the fact that its 

 leaves do not began to grow till the end of June. Here the 

 remarkable fact may be recorded that its leaf-buds are some- 

 times among the first to open in the garden. Many tender 

 young leaves were exposed in April 1890 and 1891, the 

 latter a very backward season, hut they made no further 

 progress till far on in June. 



