Mar. 1892.] THE BOTANICAL SOCIETY OF EDINBURGH. 



309 



trees, and was restricted to 0'05 in four, on an average 

 annually. Half an inch was attained in only three instances 

 — Populus fastigiata, 0*50 and O^GO, and Salix, O'oO ; 

 but Cratccgus reached 0'45 ; and Fojndus (twice), Fagus 

 (twice), Cratccgus, Salix, Quercus, 0"40. 



The total August growth was 3-95 in 1887, 4-75 in 

 1888, 6-80 in 1889, 515 in 1890, and 7-70 in 1891. 



SciJtemhcr. Growth failed entirely on an average in twelve 

 of the thirty trees annually, and reached only 0"05 in 

 thirteen, so that an annual average of only five in thirty 

 attained 010 or upwards. Some substantial increases 

 occurred, however, Salix reaching 0"20 and O'oO, Cratwgus 

 0-20 and 0-25, and Prunus 0-25. 



The total September increases were 1*00 in 1887, 1'05 

 in 1888, 1-50 in 1889, 1-90 in 1890, and 1-60 in 1891. 



h. Monthly Proportion of Girth-increase in thirty Deciduous 



Trees, collectively. 



Table V. Percentage of Aggregate Monthly Girth-increase 



IN thirty Deciduous Trees for five years, 1887-1891. 



The aggregate results for the five years show that the 

 chief growth took place in June and July, June having only 

 a slight advantage over July. In round numbers, together 

 they account for rather more than three-fifths of the whole 

 increase, August follows with one-fifth. May with about 

 one-eighth, September with a twentieth, and April with 

 only about a sixty-fifth. 



The monthly range of p.c. in the five years was from O'O 

 to 2-5 in April, 7 to 18 in May, 25 to 40 in June, 26-5 

 to 32-5 in July, 15 '5 to 28*5 in August, and 4 to 6 in 

 September. 



