Nov. 1892.] BOTANICAL SOCIETY OF EDINBURGH. 



17 



elements of doubt remain. I have shown, in the first 

 place, that the giants of other species probably grow at a 

 quite exceptionally rapid rate, and that this is possible in 

 the yew also is indicated by the exceptional rate of 0"84: 

 for the first 112 years of life in one recorded by Mr. 

 Bowman. Secondly, from Sir E. Christison's own observa- 

 tions on the lars^e Craigiehall beech and the Fochabers 

 Scots fir, it is plain that the falling off in rate, which in 

 average trees begins before they have attained a large size, 

 in trees destined to be great may be put off till they have 

 assumed almost gigantic proportions. Hence, it is quite 

 possible that Sir E. Christison's estimate of 1000 years 

 for a tree 22 feet in girth may be several centuries in 

 excess of the truth. The question might be solved by 

 using the modern instruments which extract cylinders to 

 a considerable depth, whereas Mr. Bowman's primitive 

 borer only probed to a depth of a few inches. 



Sir Eobert's estimate of 3000 years for the age of the 

 Fortingall yew may in a corresponding way be liable to 

 great reduction. 



Finally, it may be a question whether gigantic stems 

 like these may not be compound — formed by the 

 coalescence of two or more which were originally separate. 



III. The Cedar (Ccdrus Libani). 



As the cedar somewhat resembles the yew in the 

 varieties of form in the stem, I have given the girth at 

 several points, so as to give a better idea of the true 

 size of the specimens recorded. 



Scottish cedars above 17 feet in girth at different 

 heights, from Mr. Hutchison's Table of 58 Scottish cedars 

 (Trans. H. and Ag. Soc. Scot., 1890). 



* Blown or cut down in a dying state lately. 

 60 to 70 feet in height, . . . .14 

 70 ,, 80 „ .... 4 



80 ,, 88 „ .... 5 



TRANS. BOT. SOC. EDIN. VOL. XIX. 



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