Nov. 181)2.] BOTANICAL SOCIETY OF EDINBUUGII. 523 



enormous bulk of the trees as it is likely to have done at 

 any previous period, except in very early life. And if it be 

 true that the species was only introduced in Scotland about 

 the year 1600, then these trees must be a little under 

 three centuries old, and they must have increased nearly 

 at the rate of an inch a year (0"92 and 0"93), at 5 feet 

 above ground, over that long period. The measurements, 

 quoted by Mr. Hutchison, at three points in 1817, 1832, 

 and 1882, yield results which, on the whole, agree so well 

 with each other as to inspire considerable confidence in 

 their accuracy. The only exception is the remarkably 

 rapid rate, at one foot up, between 1817 and 1832, both 

 in " Adam " and " Eve," but particularly the former. This 

 may have been due to a sudden expansion in the conoid 

 base, which I have been led to believe, in the present 

 investigation, is apt to take place in very large trees of 

 various species, and which is occasionally confirmed by the 

 rings in tree-sections ; or it may be an error of observation, 

 as at 1 foot up the slightest shifting in position of the 

 tape may give very different results. Strutt (Sylva Brit., 

 1826) gives 268 inches at 1 foot and 209 at 5 feet as 

 the girths of one of these trees. Comparing these with 

 the figures for 1817 in the table, and supposing Strutt's 

 figures to date from 1825 for "Adam," the larger of the 

 two, we get 3 "7 5 for the rate at 1 foot, and 1"87 at 5 feet, 

 for the eight years 1817 to 1825, which agree wonderfully 

 well with the corresponding rates of 3*18 and 1'50 from 

 1818 to 1833 in the table. 



V. The Spruce Fir (Abies excdsa). 



Notices of large spruce firs are not nearly so numerous 

 as of the silver fir, although the two species were introduced 

 about the same date. I have only two to offer, both taken 

 from the Conifer Conference Statistics of 1891. 



