KEY, BASED UPON FLOWERS. 7 



Very oblique, branchlets brown and rough 148. P. CONTORTA. 



Not oblique, branchlets purple, quite smooth 98. P. INOPS. 



/ 2 . 2-3 in. long; cone 2-2-J- in. long. 122. P. CT,AUSA. 



/ 3 . 3-5 in. long, sheaths elongated, cones 

 ff. Scarcely 2 in. in length, solitary or in pairs and slightly if at all oblique; 



branchlets 

 Rough; prickle inclined nearly at right angle to the axis of cone when 



closed 75. P. MITIS. 



Smooth ; prickle inclined more towards the apex of the cone. 



123. P. GLABRA. 



gr 2 . 2-3| in. long, mostly in umbels, very oblique 170. P. MURICATA. 



rf 2 . Leaves in 3s and scales of cone thickened at apex and 

 e. Armed with a prickle or spur ; leaves 



/. 3-6 in. long, cone about 2 in. long; prickles strong 50. P. RIGIDA 



/'. 5-8 in. long ; cone 2-3 in ; prickles weak 121. P. SEROTINA. 



/ 2 . 7-10 in. long, stout ; cone 3-5 in. long, sessile 147. P. PONDEROSA. 



/ 3 . 8-15 in. long ; cones 



4-8 in. long, oval, lateral long-stalked 198. P. SABINIANA. 



6-10 in. long, subterminal, slightly if at all oblique. 



124. P. PALUSTRIS. 



10-15 in. long, lateral, very oblique and heavy 169. P. COULTERI. 



e-- Unarmed at maturity, very oblique and scales very gibbous outside near 



the base 199. P. RADIATA. 



(1 3 . Leaves in 5s ; scales of cones 

 e. Thin and unarmed 



4-6 in. long 49. P. STROBUS. 



12-18 in. long 146. P. LAMBERTIANA. 



e 2 . Thick and armed with a thick spur 197. P. TORREYANA. 



d*. Leaves in both 2s and 3s, 7-12 in. long ; cone 3-6 in. long, glossy brown. 



125. P. CUBENSIS. 



c 2 . Leaves evergreen, scattered (not fascicled) ; cones with 



<L Thick scales, maturing the second year 196. P. MONOPYLLA. 



d -. Thin scales, maturing the first year. 



e. Cones erect ; cylindrical ; leaves mostly flat, linear (Abies.) 

 f. Cones 3-4 or 5 in. long ; leaves 



Scarcely 1 in. long 22. A. BALSMEA. 



2 in. or more in length 173. A. CONCOLOR. 



f' 2 . Cones 6 or 8 in. long ; leaves quadrangular 174. A. MAGNIFICA 



e 2 . Cones pendent. 

 f. Bracts inconspicuous, leaves 

 (/. Petiolate and generally flat and linear (Tsuga); cones 



Small, | in. or less in length, leaves 2-ranked.: . . .21. T. CANADENSIS. 



Larger, 2-3 long ; leaves scattered 171. T. PATTONIANA. 



</ 2 . Sessile ; leaves 4-angled (Picea) 



1-H in. long, ovate, scales eroded at tip, branchlets pubesent, 



20. PICEA NIGRA. 

 *2 in. long, cylindrical-ovoid, entire at tip, branchlets smooth 



100. PICEA ALBA. 

 1^-3 in. long, cylindrical, scales elongated and incisely denticulate at 



tip 149 . PICEA SITCHENSIS. 



/*. Bracts conspicuously exserted (Pseudotsuga) ; cone 



2-3 in. long 150. P. TAXIFOLIA. 



5-8 in. long 172. P. MACROCARPA. 



c 3 . Leaves deciduous, soft, needle-shaped and in fascicles of many each ; cones 

 about 8 lines in length, scales thin (Larix) and with inflected margins 



23. L. AMERICANA. 

 6 2 . Few, 

 c. Imbricated, without bracts and each bearing two erect ovules ; flowers 



d. Monoecious, scales thinnish and 8-12 (Thuya) 24. T. OCCIDENTALS. 



d 2 . Dioecious, scales fleshy and consolidated making a dark blue berry-like 



fruit (Juniperus) which is 



Large (about } in.), reddish-brown with sweet fibrous flesh ; seeds 1 or 2. 



167. J. CALIFORNICA. 



