330 TRANSACTIONS AND PROCEEDINGS OF [Sess. i.vi. 



is nearly an equality ; and in two the advantage lies with 

 the second period. The extremes are — Araucaria, with 73 

 p.c. in the first period, and Ccdrus Dcodara, with 66 p.c. in the 

 second. 



Of the species that occur in both groups the proportions in 

 Araucaria are almost identical, and in the three others there 

 is at least no violent contrast. 



The proportions of Araucaria, Cupressus, P. excclsa, Ah. 

 Dour/lasii, Ab. Lovnana, Sequoia, Taxus, and Ccdrus Dcodara 

 may be considered as well ascertained in a general way, the 

 differences between numbers of the same species in the older 

 and younger groups being perhaps due to differences in age. 

 The results in the others require confirmation, as they rest on 

 measurements of single specimens. 



III. General Eemarks. 



Length of the Growing Season. — This can only be indi- 

 cated in a rough kind of way by observations at monthly 

 intervals. I have given it as including the six months from 

 April to September ; but although it is true that girth- 

 increase may go on in the trees as a body during the whole 

 of this period in a favourable season, it is certainly excep- 

 tional for any tree individually to occupy so much time, and 

 probably the majority get over their growth in less than five 

 months. In a paper founded upon weekly observations 

 (Trans, and Proc, 1891, p. 103), I have discussed this 

 question fully, and have shown that in the highly favourable 

 season of 1890 growth could be traced in Abies Lowiana, 

 No. 8, and Pinus excelsa, No. 2, for twenty- seven weeks, 

 beginning about April 6th. These are probably exceptionally 

 favourable cases. On the other hand, the very healthy and 

 vigorous yEscnlus ITippocastaoium No. 80 grew for only seven- 

 teen weeks, beginning so late as May l7th. As a rule, the 

 Coniferaj occupy a longer time than Deciduous trees, begin- 

 ning earlier and ending later. 



Progressive Pate of Girth-Increase throughout the Growivg 

 Season. — The Tables show that the great majority of the 

 trees grew from zero in spring to a maximum in summer, 

 anrl tlx'n doclinpfl to zoro in antunin, althougli rarely 



