1885.J METEOROLOGY. 381 



trees, applies only to foreigners, such as the Hungary, American, and 

 Turkish oaks. The Hungary oak is much the hardiest of all, while 

 the British oak comes out worse than other species of tree iinder 

 observation. 



Whilst the average growth of all the evergreen trees declined from 

 0-80 in. in 1880 to 0-68 in 1881, the average growth of the five 

 yews under observation rose from 0'35 in. in 1880 to 0'40 in. in 

 1881 ; thus during three severe winters following the deciduous 

 growth, and aiot their relatives the evergreen Pinacew. 



Sir Eobert confined the growth of wood in leaf-shedding trees to 

 June, July, and August. But the May growth of the three Hungary 

 oaks specially brings it up in 1 8 8 to 1 2 per cent, of the whole. 

 Again, after the unusually mild winter of 1882, it was 21 per cent, 

 of the annual increase. For the whole twenty-five trees, other than 

 tlie Hungary oaks, the average growth in May was 12 per cent, of 

 the annual increase ; but including the three Hungary oaks, it was 1 6 

 per cent. A slight and almost immaterial growth appears to have 

 occurred in August and September. 



In the evergreen trees, a considerable proportion of their annual 

 increase takes place in May, averaging from 34 to 35 per cent. Of 

 six selected trees, only the African cedar was shown to be much less 

 than in September. They apparently accomplish the greater part of 

 their growth by the end of June, so much as 63 per cent, having 

 been made. Apparently, then, heat alone does not regulate the 

 growth of wood in many evergreen trees. But further observations 

 are required to determine tlie best growing months for each class of 

 trees. July appears best for deciduous, and May for evergreen 

 trees. 



But looking at individual species, the Hungary oak begins to grow 

 earlier than any other of the species. The Turkish and American 

 oaks seem also to be early growers. The British oak grows poorly 

 in this district. The beeches made only 12 per cent, of growth in 

 May, about half the proportion of the foreign oaks. Ash and 

 hornbeam, and other deciduous species, showed an appreciable 

 growth in May. But the horse chestnut leaves were destroyed in 

 1882 by early frost and the ravages of insects. 



No less than 7 5 per cent, of the annual growth of the Sequoias 

 was finished growing by the end of June, their growth in August 

 being only 7 per cent. The Araucarias also grew rapidly in the 

 early part of the season, very nearly one-half of their annual incre- 

 ment being made by the end of May, and 70 per cent, by the end 

 of June. With the Deodars it was exactly the reverse, 70 per cent, 

 of their increment taking place after June. In the observations, the 

 Deodar is an exception to the general rule of early growth. The 



