Nov. 1899.] BOTANICAL SOCIETY OF EDINBUEGH 



Table V. — continued. 



251 



The Gum trees iiiaiutain nearly the same rate of growth 

 in the second period as in the first, and the Cottonwood 

 likewise ; but all other trees show a very considerably 

 diminished rate, varying, roughly, from a half to a third 

 part of the five-year rate. It seems strange that the older 

 Paraiso, a tree of at least twenty-eight years in 1885, 

 should show such a diminished rate of growth. Its annual 

 rate for the last nine years has been 17, 16, 9, 20, 21, 25, 

 30, 42, and 6 — in all 186 — millimetres; and this does 

 not look as if the tree were unhealthy. And why one Oak 

 should grow so much better than the other is also strange; 

 they are on just the same ground, and within fifteen yards 

 of each other. 



Thus far, only the monthly growths and percentages 

 of growth have been commented on, and the inequalities 

 of annual growth, due partly to the varying weather 

 of different years, partly to the advancing ages of 

 the trees, may present points of interest ; and I, therefore, 

 tabulate (Xo. YI.) the annual growth of these sixteen trees 

 for fourteen years, giving for each growing and sleeping 

 season the plus or minus average of inches of rainfall, of 

 estimated hours of sunshine, and of means of maxima and 

 minima thermometer readings, taking the first and last 

 three months of each year as growing season, and the 

 middle six months as sleeping season. 



In the first four years, the growth of evergreens is fairly 

 equal: in 1889, they show a considerable increase of 

 growth, and in that year, both in growing and sleeping 

 seasons, the rainfall was greatly in excess ; there was 

 a great deficiency of sunshine ; and temperature, generally, 

 was below normal. Then come three years of gradually 



