4 Pinaceae 



much thickened at apex into broad straight or reflexed umbos 

 terminating in minute spines; seeds oval, 16-20 mm. long, nearly 

 enclosed by the thickened rim of the dark brown wings, these 

 8-10 mm. wide. 



Delmar, San Diego County; Santa Rosa Island. 



6. P. ponderosa Dougl. (YELLOW PINE.) A large tree with very 

 thick red-brown bark; deeply furrowed and split in large plates; 

 leaves 3 in each cluster on stout branchlets, dark green, 15-25 

 cm. long; staminate cones cylindric, 35-50 mm. long, involucral 

 bracts 10-12; fruiting cones oval, 7-12 cm. long, rich brown; 

 scales thickened into a central knob terminating in compressed 

 straight or recurved umbos, awned with slender spines ; seeds 

 ovate, acute, about 8 mm. long, c'oat nearly black, rugose; wing 

 thin, pale brown, 25-30 mm. long and about 20 mm. wide below 

 the middle. 



Common on all our mountains, making up a greater part of the coniferous 

 forests. The cones usually fall during the autumn and winter after maturity. 



7. P. Jeffrey! Oreg. Com. (JEFFREY PINE.) Closely resembling 

 the preceding in foliage and habit; bark deeply furrowed, not 

 split in large plates, dark; staminate cones 3 cm. long; fruiting 

 cones oval, rather rich brown, 15-30 cm. long; seeds 8-10 mm. 

 long; wings about 25 mm. long. 



With the last, but much less common. Rather frequent in the San Ber- 

 nardino Mountains, especially about Bear Valley. 



8. P. Murray ana Oreg. Com. (MURRAY PINE or TAMARACK 

 PINE.) Becoming a rather large tree, 15-40 m. high ; bark rather 

 finely furrowed, grayish-brown; leaves 2, 25-75 mm. long, very 

 stout and rigid; sheaths 8-12 mm. long when young; staminate 

 cones with 6-8 involucral bracts, cylindric, 10-15 mm. long; 

 fruiting cones clustered or in pairs, oval or subcylindric, oblique, 

 2-5 cm. long; scales armed with slender recurved prickles; seeds 

 scarcely 2 mm. long, dark brown mottled with black; wings 

 light brown, widest above the base, tapering to apex, 12-15 mm. 

 long. 



Frequent in the upper portions of the coniferous forests. Mt. San An- 

 tonio; Bear Valley; Mt. San Gorgonio; Mt. San Jacinto. 



9. P. Sabiniana Dougl. (DIGGER PINE or SILVER PINE.) A 

 rather small open-topped irregularly branched tree; leaves 3 in a 

 cluster, drooping, light green or glaucous, 2-3 cm. long; stami- 

 nate cones oblong, about 2 cm. long, with 10-15 involucral bracts; 



