Pinus 1007 



grained, and dark-coloured ; sapwood thick, and paler in colour than the heart- 

 wood. 



D. Leaf-sheaf persistent in all the cultivated species. Leaves always 



SERRATE. 



a. Leaves in fives. 



6. Pseudostrobus, Engelmann. Leaves with median resin -canals. Cones 

 sub-terminal. Shoots uninodal. 



22. Ptnus Montezuma, Lambert. Mexico, Guatemala. See p. 1061. 



Branchlets stout, not glaucous, reddish brown. Buds ovoid, pointed, an 

 inch long, reddish brown, scarcely resinous. Leaves about 9 in. long ; basal 

 sheaths i|to 2 in. long. Scale-leaves persistent. 

 22A. Pinus Montezuma, Lambert, var. Hartwegii, Engelmann. Cold regions 

 and high altitudes of Mexico. See p. 1062. 

 Branchlets and buds, as in the type, but the latter smaller, \ to in. long, 

 usually with resinous appressed scales. Leaves 5 to 6 in. long ; basal sheaths 

 1 in. long. Scale-leaves persistent. 



23. Pinus pseudostrobus, Lindley. Mexico. See p. 1064. 



Branchlets slender, glaucous. Buds, leaves, and scale- leaves as in 

 P. Montezuma. 



24. Pinus Torreyana, Parry. Coast of California near San Diego, and Santa 



Rosa island. See p. 1065. 

 Branchlets glaucous, dull grey in the second year. Buds cylindro-conic, 

 \ in. long ; scales pale brown with appressed points. Leaves 7 to 1 3 in. long, 

 very stout ; basal sheaths an inch long. Scale-leaves deciduous. 



. Leaves in threes. 

 7. Taeda, Mayr. 



Leaves with median resin -canals. Cones variable in size and position. 



Shoots uninodal or multinodal. 



* Buds resinous ; points of bud-scales appressed. 

 f Leaves more than 6 in. long. 



25. Pinus Coulteri, Don. California. See p. 1067. 



Branchlets stout, glaucous, remaining green in the second year. Buds 

 ovoid, stout, acuminate or cuspidate, 1 to i| in. long. Leaves 10 to 14 in. 

 long, dark green, spreading from the upper part of the branchlets of the first 

 and second years. 



26. Pinus Sabiniana, Douglas. California. See p. 1069. 



Branchlets slender, glaucous, remaining green in the second year. Buds 

 narrowly cylindrical, an inch long. Leaves 7 to 12 in. long, greyish green, 

 spreading or drooping from the upper part of the branchlets of the first and 

 second years. 



27. Pinus ponderosa, Lawson. Western N. America. See p. 107 1. 



Branchlets stout, reddish, not glaucous, becoming nearly black in the second 



