372 A HANDBOOK OF CONIFER.E 



Winter buds conical, resinous, about ^ in. long, scales long- 

 pointed and free at the tips. Leaves in fives, spreading, usually 

 persistent for 3 years, slender, 4-8 in. long, margins finely 

 toothed, apex pointed, inner surfaces flat with 3-4 lines of stomata, 

 no stomata on outer surface ; resin canals marginal ; basal sheath 

 deciduous. Cones sub -terminal, large, sohtary or clustered, 

 cylindrical, tapering at the apex, 8-18 in. long, 2|-6 in. wide at 

 the base when expanded, on stalks 1-2 in long ; scales ovoid, 

 2-3 in. long, 1-1 1 in. wide, the enlarged tip resinous and often 

 reflexed, basal scales reflexed. Seed ovoid, about f in. long, 

 usually with a well-developed wing. 



Var. brachyptera, Shaw. 



P. strobiformis, Engelmann. 



Differs from the type in its very short and ineffective seed- 

 wing and its abnormally large seed. 



Var. Veitchii, Shaw. 



P. Buonapartea, Roezl ; P. Loudoniana, Gordon ; P. Veitchii, Roezl. 



Differs from the type by its large cones, comparatively short 



seed-wing (about | in. long), and by its larger seeds (^ in. long). 



On vigorous young trees the leaves may be more than 5 in a 



cluster. 



This species, although very variable in foliage and cones, is 

 generally recognized by its large cones with reflexed basal scales. 

 It resembles P. excelsa in foliage, but can usually be distinguished 

 by the downy young shoot. The cones of the two species are 

 often very similar in size and outhne, but P. Ayacahuite can 

 be distinguished by the distinctly reflexed basal scales. Trees 

 growing in the southern part of its range are said to bear seeds 

 with the longest wings, the wings being gradually reduced in size 

 as its most northerly latitude is approached. 



P. Ayacahuite is found on mountain slopes, and at the heads 

 of ravines in Cent. America, extending from Guatemala through 

 Mexico to the United States border. Discovered by Ehrenberg 

 in Mexico in 1836. 



Little is known of the wood in this country, but from an 

 examination of small specimens it would appear to compare with 

 that of P. excelsa and to be suitable for similar purposes. It is 

 used with that of other Mexican pines for general carpentry and 

 for joiners' work, and probably has a bearing upon the rather 

 small turpentine and rosin industry of that country, an industry 

 that is stated to be capable of considerable expansion. 



Its wide distribution, both in latitude and altitude, has an 

 effect upon its hardiness, and trees grown in this country may 

 be hardy or tender according to the place from which seeds were 



