Note 4 — Trees and Woods of the Lignum-vitae Family
Reading edition
In a specimen (Yale No. 974) of the shrub Larrea divaricata Cav. (Zygophyllaceae) from Argentina the number of ripple marks is about 270 per inch. In this wood the ground mass is composed of small thick-walled fiber-tracheids with very abundant and prominent bordered pits. The rays are 1 to 12, mostly 6, cells high, uni-seriate or more commonly bi-seriate in the median portion; rather indistinctly storied. The wood parenchyma contains crystals some of which are large and conspicuous.