POPULTJS FKEMONTII WHITE COTTONWOOD. 51 



PHYSICAL PROPERTIES. The wood is light, tough, quite strong, 

 close-grained, and of a light reddish-brown color, with light pink is h- 

 white sap-wood, whitest near the bark. Specific Gravity, 0.4969; 

 r<'/'<-c/if <Kj<< <>f A*Ji* 0.61; Relat'tre Approximate Fuel Value, 0.4939; 

 Coefficient of Elasticity, 108507; Modulus of Rapture, 808; Resist- 

 <uire to Longitudinal Pressure, 408; Resistance to Indentation, 98; 

 Weight of a Cubic Foot in Pounds, 30.97. Of the variety 5/w////- 

 the Specific Gravity is 0.5412; Percentage of Ash, 0.39; 

 Approximate J^uel Vbi>\ 0.5391; Coefficient of Elasticity, 

 126216; 3Lo<lnln* <>f Rapture, 909; Resistance to Longitudinal 

 Pressure, 468; Resistance to Indentation, 126; Weight of a Cubic 

 foot hi Pounds^ 33.73. 



USES. Little use is made of this timber. 



GENUS POPULUS, TOURNEFORT. 



Leaves broad, more or less heart-shaped or ovate, and with long and often ver- 

 tically compressed petioles. Flowers appearing before the leaves in long, droop- 

 ing, lateral, cylindrical catkins, the scales of which are furnished with a fringed 

 margin ; calyx represented by an oblique, cup-shaped disk with entire margin ; 

 stamens, 8-30 or more, with distinct filaments ; pistil w T ith very short, bifid style, 

 and large 2-lobed stigma. Fruit as described for the order . 



Genus represented mostly by rather large trees, and the name is a Latin word, 

 meaning people, applicable either from the fact that these trees are often set 

 along public walks, or in allusion to the tremulous motion of the leaves, which 

 are in constant agitation like a crowd of people. 



194. POPULUS FREMONTII, WATSON. 

 WHITE COTTONWOOD, FREMONT COTTONWCOD. 



Ger., Weisse Pappel ; Fr.. Peuplier blanc ; Sp., Alamo bianco. 



SPECIFIC CHARACTERS: Leaves thick and firm, broadly deltoid or reniform 

 narrowing to a short entire point, truncate, slightly cordate or abruptly wedge- 

 shaped at the wide entire base, coarsely and irregularly crenate-serrate with few or 

 a dozen or more incurved teeth on each side, coated as with the petiole with pale 

 fungaceous pubescence at first but finally lustrous green, blade 2 to 3 in. long 

 and about as wide ; petioles 1 to 3 in. long, laterally compressed ; branchlets 

 terete, light green and pubescent at first, finally light yellowish gray. Floivers 

 appear in February and March in aments with glabrous rachis and bracts ; the 

 staminate, 1| to 3 in. long, densely flowered and with slender stems ; scales thin, 

 light brown," scarious, dilated and fimbriated at apex and caducous ; stamens 60 or 

 more with large dark red anthers inserted on a broad disk, 3-4 lines broad, with 

 entire margin ; pistillate aments with stouter and often puberulous stems, more 

 sparsely flowered and 3-4 in. long ; ovary ovoid or ovoid-oblong, glabrous, sub- 

 tended by the cup-shaped, membranous persistent disk ; stigmas 3, broad and 

 irregularly crenate-lobed. Fruit ovoid capsules nearly in. long, with thick 

 slightly pitted walls, stout peduncle 1 line in length, on drooping racemes 4-5 in. 

 long and dehiscent by 3 (rarely 4) valves ; seeds nearly | in. in length, ovoid and 

 copiously surrounded with long soft white cottony hairs. 



The specific name is given in compliment to the botanical explorer, Capt. John 

 C. Fremont. 



