PLATE 35- THUYA OCCIDENTALTS. Tangential section showing the very narrow 

 medullary rays with narrowly oblong cells, taken from the spring wood. 

 X 64 



PLATE 36. SEQVOIA SEMI-ERVIRENS. Transverse section showing the very large 

 tracheids of the spring wood with thin walls, the rather dense summer wood 

 with a somewhat abrupt transition from the spring wood, the scattering dis- 

 tribution of the resin cells, and the occurrence of resin sacs in the initial layer 

 of the spring wood. X 46.8 



