CUPRESSUS 235 



structure not very open. Resin cells prominent, dark, not very large 

 or numerous, rather scattering or again zonate in both spring and 

 summer woods. Medullary rays not prominent or numerous, rather 

 narrow and i cell wide, distant 1-23 tracheids. 



Radial. Medullary rays devoid of tracheids, sparingly resinous, the cells 

 straight and equal to 5-10 spring tracheids; the upper and lower 

 walls thickish, sinuately unequal, not obviously pitted ; the terminal 

 walls thin, curved or straight, not pitted or locally thickened ; the 

 lateral walls with oval, bordered pits, chiefly i, or in the marginal 

 cells 2, per tracheid, the orifice lenticular-oblong. Bordered pits 

 round or elliptical, rather distant in i row, usually less than one half 

 the diameter of the tracheid. Pits on the tangential walls of the 

 summer tracheids not very numerous, small, flat, obscure. Resin 

 cells few, 15-25 /j, wide, 150-210 p. long, chiefly about 150 /x. 



Tangential. Rays medium, narrow ; the uniformly oval, nonresinous cells 

 rarely if ever in pairs. 



B. CUPRESSUS 



6. C. macrocarpa, Gordon 



Monterey Cypress 



Transverse. Growth rings usually broad. Summer wood very thin, of 6-8 

 tracheids, and passing gradually into the spring wood from which it 

 is not always clearly separable. Spring wood very broad, the tra- 

 cheids uniform, rather large, rounded-hexagonal, the walls rather 

 thick. Resin cells prominent and widely scattering or somewhat 

 zonate in the summer wood. Medullary rays prominent, resinous, 

 broad, i cell wide, distant 2-12, rarely 33, tracheids. 



Radial. Rays devoid of tracheids and resinous throughout. Cells more or 

 less contracted at the ends, equal to 4-6 spring tracheids ; the upper 

 and lower walls variable and not obviously pitted ; the terminal walls 

 thin, often curved, locally thickened ; the lateral walls with rather 

 large bordered pits with large, lenticular, or oblong orifices, 1-2, or in 

 the low rays 4, per tracheid. Bordered pits round or elliptical, some- 

 times in pairs. Pits on the tangential walls of the summer tracheids 

 numerous, large, and open. Resin cells not numerous, 20-25 P- wide, 

 40-65 p. long, chiefly about 50 p.. 



Tangential. Rays medium, sometimes 2-seriate in part, the cells broadly 

 often transversely oval, thick-walled. 



This species is usually recognized by the very large, bordered pits on the 

 tangential walls of the summer tracheids. In transverse section the 

 summer wood commonly presents somewhat strong variations in speci- 

 mens from different individuals. 



Wood heavy, hard, strong, and very durable. Trees upward of 21 m. in 

 height and i .80 m. in diameter. 



Relative specific gravity 0.6261 



(Sargent) 



California (Sargent). 



