214 ANATOMY OF THE GYMNOSPERMS 



Damp woodlands from Newfoundland westward to Lake Winnipeg and 

 Minnesota, northward to York Factory, and southward to New Jersey 

 or along the Alleghenies to Virginia. 



The Pleistocene of the Don River, Toronto ; Solsgirth and Heart Hill, 

 Rolling River, Manitoba, and Fort Madison, Iowa ; Cape Breton and 

 Bloomington, Illinois. An abundantly represented and widely dis- 

 tributed species in the northern United States and southern Canada. 



3. T. brevifolia, Nutt. 



Yeiv. Western 



Transverse. Growth rings thick, upwards of 2-3 mm. Summer wood 

 dense, about equal to the spring wood into which it passes very 

 gradually. Spring wood open, the tracheids in regular rows, rather 

 uniform, not much rounded. Medullary rays I cell wide, distant 

 about 1-17 rows of tracheids. 



Radial. Ray cells very long ; the upper and lower walls thickish, unequal, 

 conspicuously double, entire or distantly pitted ; the terminals walls 

 thin and entire ; the lateral walls with round, conspicuously bordered 

 pits, chiefly 2, more rarely 4, per tracheid, the narrow diagonal orifice 

 equal to the outer ring. Bordered pits round or elliptical. Pits on 

 the tangential walls of the summer tracheids numerous but very small 

 and obscure. Spirals of the tracheids prominent, 2-seriate, distant 

 7.5-20 fj., rarely more, the angle 63.0, vestigial in the summer wood. 



Tangential. Rays commonly high, the cells thick-walled. 



Very durable in the soil. 



Relative specific gravity ........... 0.6391 



Approximate fuel value ............ 63.78 



Coefficient of elasticity in kilograms on millimeters . . 761. 



Ultimate transverse strength in kilograms ..... 460. 



Ultimate resistance to longitudinal crushing in kilograms 7734. 



Resistance to indentation to 1.27 mm. in kilograms . . 4223. 

 (Sargent) 



Vancouver Island and adjacent mainland and on the lower Skeena 

 (Macoun) ; sparingly in the Queen Charlotte Islands (Dawson) ; south- 

 ward through the coast ranges of British Columbia, Washington, and 

 Oregon, the western slopes of the Rocky Mountains in Montana, and 

 through the California coast ranges to Monterey and the southern slopes 

 of the Sierra Nevadas to latitude 37 N. (Sargent). 



4. T. cuspidata, Sieb. et Zucc. 

 Yew. Jap. = Araragi 



Transverse. Growth rings rather broad. Summer wood prominent, about 

 one fourth the spring wood into which it passes gradually. Spring 

 wood somewhat open, the tracheids distinctly hexagonal, rather 



