THE BOTANICAL MAGAZINE. 



[Vol. XXXIY. No. 403. 



No. 



Names of Trees 



Habitat 



Numbers Average 

 of Annu- radii 









al rings 



(cm.) 



VIII 



Cryptomeria japonnica, Don. 



Yakujima (Osumi) 



240 



78.1 



IX 



)) >' » 



Ise 



193 



30.8 



X 



» V )} 



Yakujima (Osumi) 



1600 



124.5 



XI 



)j j> a 



Mt. Amagi (Idzu) 



680 



65.0 



XII 



Chamaecyparis oliitosa, S. et Z. 



Arisan (Formosa) 



375 



41.7 



XIII 



Tsuga diversijlora, Maxim. 



Nikko (Shimotsnke) 



196 



18.7 



XIV 



Firms densiflora, S. et Z. 



Osaka 



132 



32.5 



XV 



Fagus japonica, Maxim. 



Nikko (Shimotsuke) 



106 



14.6 



XVI 



Quercus crispula, Bl. 



y> )) 



225 



31.3 



XVII 



}> >} » 



?> » 



256 



32.9 



XVIII 



Betula ulmi folia, S. et Z. 



» 5J 



140 



23.5 



XIX 



Acer picium, Trusts. 



JJ » 



207 



19.0 



SECTION I 



Growth in Thickness 



I have measured the thickness of each annual ring in cross section 

 of trunks of these trees. If the sections were circular and concentric, 

 the measurements were made in only one radius, while if they were 

 excentric, in radii, the shortest and the longest, and then the average 

 was taken. These numerical data of my measurements, however, can 

 not be set down in the present paper, on account of want of space. 



A. Type of the growth in thickness 

 I. Cryptomeria japonica, Don. 



In Cryptomeria japonica, one of the most important timber trees 

 in Japan, the determination of the mode of growth has already been 

 made by Dr. Honda, 1 Dr. Terasaki 2 and others. It was made, how- 

 ever, of planted trees of about 100 years old. 



1. Honda, S. (1896) Ertragstafel und Zuwachsgesetz fur "Sugi", zum Gebrauch 

 fur japanischer Forstmanner. — Bull. Col. Agr. Tokyo, vol. 2. 



2. Terasaki, W. (1914) Growth and product of woods of Cryptomeria japonica. 

 — Eep. For. Exp. Stat., No. 11, (Japanese). 



