sept, mo.] SUZUKI-ON THE STRUCTURE AND AFFINITIES 183 



are enclosed in the dark brown contents within the tubes. These 

 contents suggest the slime which once filled the tubes. The 

 appearance of the crystal tubes is just like that of Ahietinese 

 (Prantl 10) where the monoclinic crystals of calcium oxalate 

 are imbedded in slime within the tubes. Optical as well as 

 chemical tests have been tried with these crystals, but I am 

 not yet in a position to decide whether they are calcium oxalate 

 as in living Ahietinese. Their further study is left for future. 



Unfortunately, the region of the cambium and its adjacent 

 part of the phloem is not preserved and is filled with the 

 deposit of iron pyrites. 



Wood. The wood has about 16 annual rings which in- 

 dicate very irregular zones of development. We see only 2 

 normal resin canals in the second annual ring formed by a 

 fascicular cambium, whose activity of forming secondary wood 

 in the first year was very slight ; we do not find any other 

 resin canals in the transverse as well as longitudinal sections 

 except several traumatic resin canals tangentially arranged in 

 an outer annual ring in a transverse section. 



The tracheids of spring wood are, as seen in transverse 

 section, thin walled and angular, but the tracheids of autumn 

 wood are thick walled and roundish. 



The tracheids show bordered pits on the radial walls, but 

 in the thick walled tracheids of autumn wood, we see some- 

 times simple pits sparsely arranged. These simple pits are 

 roundish, elliptical, lenticular or slit-like, and some autumnal 

 tracheids seem to have no pits at all. 



The bordered pits are mostly arranged in a single row and 

 rarely in double rows on the wider tracheids of the spring 

 wood. In the latter case, they are generally opposite. The 

 orifice of bordered pit is roundish. 



The medullary rays are generally one cell broad and 1 — 2 cells 

 in height, though even 18 cells high medullary rays may occur. 



The walls of ray cells are thin and smooth, and are pitted 

 simply in the radial, tangential and horizontal walls, and they 

 present no serration like those in Pinus. The pits on the 

 radial walls adjoining to the broad tracheids are generally 



