CUPRESSUS 



237 



chiefly straight, locally thickened ; the lateral walls with oval or round 

 bordered pits, orifice lenticular, 1-2, or in the marginal cells rarely 3, 

 per tracheid. Bordered pits rather numerous in i row, elliptical, the 

 orifice large. Pits on the tangential walls of the summer tracheids 

 rather numerous and large, the orifice bell-shaped, not very open. 

 Resin cells not numerous, 12.5-25 or sometimes 35 p. broad, 210- 

 310 p. long, chiefly about 250 /x. 

 Tangential. Rays low, the cells broad, oval, or round, often resinous. 



A small tree of the mountains of Lake County, California (Sargent). 



9. C. Goveniana, Gordon 



Cypress 



Transverse. Growth rings variable. Summer wood very thin, of 2-6 

 tracheids ; the transition to the spring wood gradual. Spring wood 

 very open, the tracheids large and squarish, in regular rows, rather 

 uniform and thin-walled. Resin cells abundant and prominent, in 

 narrow but well-defined zones, sometimes forming rather extended 

 radial series, i to 3 cells wide, of broader and thicker-walled cells. 

 Medullary rays rather numerous but not very resinous or prominent, 

 i cell wide, distant 2-8, rarely 15, tracheids. 



Radial. Rays devoid of tracheids, more or less resinous. Ray cells con- 

 spicuously narrower at the ends, equal to 3-8 spring tracheids, becom- 

 ing shorter in the summer wood ; the upper and lower walls medium, 

 entire or distantly pitted ; the terminal walls thin, often locally thick- 

 ened ; the lateral walls with round or oval pits having large, round or 

 oval openings, 1-2, or in the marginal cells 4, per tracheid. Bordered 

 pits elliptical, sometimes round in I row, becoming much more dis- 

 tant and smaller toward the summer wood. Pits on the tangential 

 walls of the summer tracheids rather numerous, prominent, chiefly 

 large and open. Resin cells rather abundant, 10-20 p, wide, 185-375 fj. 

 long, chiefly about 225 //, ; sometimes in radially wide, multiple series 

 of broad and short, thick-walled cells. 



Tangential. Rays low and broad, sometimes 2-seriate in part ; the cells 

 thick-walled, chiefly transversely oval. 



This species is largely distinguished by the smaller pits on the lateral walls 

 of the strongly contracted ray cells, and by the transversely oval ray cells 

 as shown in tangential section. 



A small tree furnishing a light, soft wood. 



Relative specific gravity 0.4689 



Approximate relative fuel value 46.68 



Coefficient of elasticity in kilograms on millimeters . . 499. 



Ultimate transverse strength in kilograms 230. 



Ultimate resistance to longitudinal crushing in kilograms 5742. 



Resistance to indentation to 1.27 mm. in kilograms . . 2852. 

 (Sargent) 



Humboldt County, California, south along the coast, and through the coast 

 ranges into southern California (Sargent). 



