Mar. 1892.] THE BOTANICAL SOCIETY OF EDINBURGH. 281 



the five years. The amount in its best year, 1'75, shows 

 what it is capable of doing even in a very poor soil. 



No. 74. Acer Pseudo-platanus, 1'12 ; No. 19, Cratcvgus 

 Oxyacantha, 1-06 ; No. 78, Bctula alba, 1-05. These results 

 are probably reliable, as the trees are fine specimens ; never- 

 theless, the great range in 74 (0'70 to 1*55), and in 19 

 (70 to 1*65), suggest that, possibly from temporary depres- 

 sions, or from the thin sandy nature of the soil, the averages 

 may be abnormally low. 



A second Acer, No. 71, is close up to 74, with 1-09 ; but a 

 ^Qcondi Betula, with "8 8, falls behind No. 78, notwithstanding 

 a better situation, perhaps from greater age, its girth being 

 above 2 feet. 



No. 61. Quercus rubra. A very young tree, just recovering 

 from transplantation. Probably its rate will soon exceed 

 the 0"95, which is that of the last two years. 



No. 79. Pyrus Auc7iparia, 0*94, probably a reliable result, 

 as the tree is in good soil, is vigorous and healthy-looking, 

 and the range is not great. 



No. 23. Fraxinus excelsior, 0'91, is rather low compared 

 with the rate of some forest species, but the specimen is 

 favourably situated, seems quite healthy, and the range is 

 small. 



No. 88. Alnus glutinosa, 0*82; apparently reduced by 

 failure of health in the last two seasons. In poor sandy 

 soil. 



No. 21. Cytisus Laburnum, 0"82, reliable as far as the 

 healthy appearance of the tree goes, but it is in thin sandy 

 soil. 



No. 70. Quercus Robur, 0*81, seems good for an Oak, in a 

 district where that species does not greatly flourish. It is 

 nearly twice as high as the average of three other specimens, 

 near No. 70, but they are obviously inferior in development, 

 and suffered more than it from an insect plague in 1888. 

 All these Oaks are in the almost pure sand of the south 

 border of the Arboretum. 



No. 81. Carpinus Bctulus, 0*69, seems a low rate, 

 but it exceeds that of a neighbour. No. 86, which is 

 only 0*55. In both the foliage latterly was rather small 

 and shabby. 



No. 69. Tilia europcea. 0"68 in this, and "52 in a neigh- 



TRANS. EOT. SOC. EDIN. VOL. XIX. Z 



