1884-85.] Edinburgh Naturalists' Field Club. 223 



must be added, however, that several authorities believe this esti- 

 mate to be excessive. The following remarks on the growth and 

 decay of Yews, and the probable age of the Fortingall Yew, have 

 been courteously contributed by Mr J. Gordon, late forester at 

 Luss, who was a culJahorateur with Sir Robert Christison during 

 the investigations of the latter just referred to : — 



" The vagaries of the growth of Yew-trees are numerous, and go 

 far to invalidate the most praiseworthy efforts to evolve a factor 

 unknown in a particular tree by means of corresponding well- 

 known factors in Yews generally. It is so difficult, for instance, 

 to compute the age of a very old Yew which does not itself afford 

 ready means for computation, that blame can scarcely be said to 

 attach to failure. Tlie results of the late Sir Eobert Christison's 

 labours to compute the probable age of the venerable Yew at 

 Fortingall, Glenlyon, will have astonished many and convinced a 

 few. For myself, I feel neither astonished nor convinced, but 

 consider these results such as must always be expected from a 

 trained intellect operating upon incomplete data. In the paper 

 read to the Botanical Society in 1879, Sir Robert gives not the 

 slightest indication why the Yew at Fortingall decayed from the 

 top downwards, nor why its trunk exhibited two lunate shells 

 bearing on their convex sides a crop of living, growing branches. 

 Nor does he indicate why he preferred to adopt for his purpose the 

 smaller of two different recorded measurements. It is too evident 

 that, with the data and methods of Sir Robert, conjoined with an 

 unaccountable preference for the larger measurement of Pennant, 

 one could easily add a few centuries to the age which the late 

 Baronet has ascribed to this tree, provided the actual facts were 

 not allowed to regulate the argument. 



" The manner of its decay seems to prove this tree's manner 

 of growth in a way not dealt with by Sir Robert. It seems to 

 have had originally two adjacent separate stems, which coalesced 

 as growth advanced. These two stems would continue separate at 

 the top, while forming one undivided trunk near the ground. In 

 such a case — far from uncommon — the point of divergence of the 

 coalesced stems is notably prone to generate decay,— a fact regard- 

 ing -which I am prepared to satisfy the most incredulous, but of 

 which the bulky literature of this curious old Yew takes no notice. 

 The accounts of the progressive widening of the gap between the 

 two shells of trunk are very suggestive. At one time the gap is said 

 to admit the passage of a boy through it ; at another time a coacli- 

 and-four could pass through it. Later, the size of the gap has 

 become so indefinite that Strutt can venture to figure an entire 

 funeral cortege as in the act of strutting through it ! Now, without 

 reading between the lines of these various accounts, it is not too 

 much to state that among the purposes to be served by them, 



