1918] _  BUCHHOLZ—PINUS 209 
THE LATER EMBRYO 
In embryos of P. Banksiana, the size of fig. 47, the apical cell 
may usually still be found, but by the time the stage shown in fig. 
51 is reached it has disappeared. The cylindrical mass of cells 
L I K J G 
Fic. 3.—Development of stem tip and cotyledons: dotted line aici tees 
of root tp: shaded area, meristem of stem tip; H, J, J, K, fusing cotyledon: 
enlarges, and about the time the stage shown in fig. 52 is reached 
the cells near the tip begin to organize into an arch, shown by the 
dotted line of text fig. 34. Under this arch is the plerome of the 
root tip, the first body region to appear. The periblem organizes 
outside of this dome and is thickest above it on the side toward the 
Suspensor, where it merges with the tissue of the massive root 
