448 



Journal of Agricultural Research 



Vol. I. No. 6 



Family. Genera. 



Cupuliferae or Fagaceae Castanea, Fagus, Quercus. 



Juglandaceae Hicoria Juglans. 



Papilionaceae Robinia. 



Magnoliaceae Liriodendron, Magnolia. 



Moraceae Morus, Toxylon. 



The arrangement of wood parenchyma cells in the annual ring has 

 been divided * into three different types, as follows : 



1. Terminal parenchyma, which is situated at the periphery of the annual growth 

 ring, on the outer face of the summer wood. 



2. Metatracheal or diffuse parenchyma, which is scattered among the other ele- 

 ments in the ring, usually forming tengential bands. 



3. Paratracheal or vasicentric parenchyma, or parenchyma cells, aggregated around 

 the vessels. 



TABLE I- Native woods grouped according to the degree of tylose development and the 

 most marked distribution of wood parenchyma in ring. 2 



ABUNDANT TviosEs. 3 



MANY TYLOSES. 



SCATTERED TYLOSES. 



In Bot. Gaz., v. 53, no. i, p. 50-58, 



1 Jeffrey, E.G. A Natural Classification of Woods. 



Holden, Ruth. Some features in the anatomy of the Sapindales. 

 pi. 2-3. 1912. 



2 The data here given concerning the distribution of parenchyma were obtained from: (i) Solereder, 

 Hans, op. cit.; (2) Jeffrey, E. C., op. cit.J and (3) from original observations made during the study. 



3 By "abundant" is meant a very large number. "Many" is used to signify a considerable number 

 but less than "abundant." 



