PINACE^ 411 



visible with a lens, apex short-pointed, stomatic lines on each 

 surface ; resin canals median with an occasional internal one ; 

 basal sheath | in. long, soon deciduous. Cones sub-terminal or 

 lateral, solitary or several together, ovoid, 11-21 in. long, on 

 slender stalks |-| in. long, ripening during the third year, and 

 often remaining unopened on the branches for several years ; 

 scales f in. long, f in. wide, the hidden part dark brown, the 

 exposed part light brown, terminated by a minute prickle which 

 usually falls early. Seeds oval, light brown with a rough, mottled 

 surface, ^ in. long, wing | in. long. 



Var. Chihuahuana, Shaw, 



P. Chihuahuana, Engehnann. 



A northern form differing from the type in its stouter, more 

 rigid leaves, which are usually in clusters of 3-4, and only occasion- 

 ally in fives. It is often regarded as a distinct species. Shaw,^ 

 however, places it under P. leiophylla, on account of its triennial 

 cone. Trees with foliage intermediate in character are known to 

 occur. 



P. leiophylla is distinguished from allied species by its tri- 

 ennial cones. 



The typical form of P. leiophylla is confined to sub -tropical 

 and warm temperate altitudes in Mexico, from Oaxaca, through 

 the central and western States to S. Arizona and New Mexico. 

 The var. Chihuahuana is found in S. Arizona and New Mexico, 

 extending S. along the N.W. Sierras to the Territory of Tepic 

 and the State of Zacatecas. 



Wood apparently of good quality, although not known in 

 Europe. 



The tree is not hardy in the British Isles. It appears to cone 

 freely and to produce abundance of seed, whilst it is almost 

 unique in the fact that it is sometimes reproduced by sprouts 

 from cut-over stumps. 



Pinus leucodermis, Antoine. (Fig. 91.) 

 Bosnian Pine. 



Pinus Laricio, var. leucodermis, Christ. 



An alpine pine closely allied to P. Laricio and resembling 

 P. Cemhra in habit. It attains a height of 90 ft. and a girth of 

 6 ft. Bark grey, dividing into irregular plates. Young shoots 

 glaucous. Winter buds like those of P. Laricio but darker brown 

 in colour. Leaves in pairs persisting 5-6 years, densely covering 

 the branchlets except at the base of each year's shoot which is 

 bare for a short distance, forming a cup-hke tuft ; dark green, 

 rigid, erect, 2-3 in. long, margins minutely toothed, ending in a 



^ Pines of Mexico, p. 14 (1909). 



