ABIES 



257 



and distinctly bordered. Bordered pits elliptical, in i row, nearly 

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

 summer tracheids rather numerous, not very large. Resin cells and 

 resinous tracheids wholly wanting. 



Tangential. Rays medium, the cells variable, from round or broadly oval 

 to narrowly oblong. 



A tree 20-40 m. high, with a trunk upwards of .60 m. in diameter. 

 Wood very light, soft, not strong, rather close grained, compact. 



Relative specific gravity 0.3476 



Percentage of ash residue 0.44 



Approximate relative fuel value 34-6 1 



Coefficient of elasticity in kilograms on millimeters . . 762. 



Ultimate transverse strength in kilograms 202. 



Ultimate resistance to longitudinal crushing in kilograms 4829. 



Resistance to indentation to 1.27 mm. in kilograms . . 1015. 

 (Sargent) 



Summit of House Mountain, south of Lesser Slave Lake ; abundant in 

 Bow River Pass on mountain slopes 5000-7000 feet elevation, extend- 

 ing on the line of the Central Pacific Railroad from Castle Mountain 

 to Selkirk Summit ; abundantly in the Gold and Selkirk ranges, and in 

 the Rocky Mountain region east of McLeod's Lake ; elsewhere in the 

 northern portion of the interior plateau it occurs in scattering groves, 

 generally in localities nearly reaching or surpassing 4000 feet, but even 

 in low valleys in the eastern portion of the coast ranges ; damp situations 

 in the country between Lesser Slave Lake and the Athabasca River ; 

 high, cool valleys in the Rocky Mountains, southward to the 49th par- 

 allel, reaching upward to the timber line (Macoun) ; valley of the Stakhin 

 River in Alaska, in latitude 60 N. ; through the Blue Mountains of 

 Oregon and the ranges of Idaho, Montana, Wyoming, Utah, and Col- 

 orado ; on mountain slopes and canons from 4000 (British Columbia) 

 to 12,000 feet (Colorado); rarely forming the prevailing forest growth 

 (Sargent). 



3. A. Veitchii, Lindl. 



Jap. Shirabe 



Transverse. Growth rings very variable, often very narrow. Summer wood 

 prominent but very narrow, of 3-5 squarish tracheids, the structure 

 open, or again broad and somewhat exceeding the spring wood, with 

 the structure rather open but the tracheids strongly rounded ; transition 

 to the spring wood gradual. Spring wood open, the tracheids rather 

 large, squarish, and thin-walled, uniform in regular rows. Resin cells 

 and resinous tracheids wanting. Medullary rays not prominent, i cell 

 wide, distant 1-20 rows of tracheids. 



Radial. Rays somewhat resinous in part, and wholly devoid of tracheids. 

 Ray cells chiefly straight, equal to 7-8 spring tracheids, or in the 



