2G4 



TRANSACTIONS AND PROCEEDINGS OF 



[Sess. 



AMien it seems desirable the results for the older set of 

 trees observed previous to 1887 are given for comparison. 

 The majority of these trees are in the Botanic Garden, 

 but a considerable number grow at Craigiehall, 5 miles 

 west of Edinburgh. The latter are distinguished by an 

 asterisk. 



I. Annual Eesults. 



A. History of the Species. 



(1) Deciduous Trees. 



Betula alba. 



Well sheltered in the Arboretum. No. 78 at the east 

 end of the south shelter belt ; No. 82 on the grass in the 

 hollow under the lee of the east belt. 



The annual rate of the younger tree, TO 5, is rather better 

 than that of the older one, 0*88, although the latter is in 

 the better situation and looks healthy and vigorous, seemingly 

 indicating that already, at a girth of twenty inches, the rate 

 of the species was falling oil". But the rate of the nnich 

 older Craigiehall Birch, No. 5*, five feet in girth in 1890, a 

 healthy tree, was only 0'46 for six years ; and that of the 

 once graceful weeping Birch, No. 1, in the Botanic Garden, 

 while still in fine condition, and measuring but four and a 

 half feet in girth, was only 0')!7 for four years previous to 

 the great frosts of 1879-80-81, since wlien it has been 

 reduced to 0*07. 



Both the young trees sliared in a depression of girth- 

 increase which aflected the Deciduous trees in 1888, and thus 

 their annual range was increased, but still it is not excessive, 

 amounting to from 080 to 1-35 in No. 78, and 070 to 110 

 in No. 82. The rise and fall of the two in dilferent years 

 corresponded pretty closely. 



