na.
Cones less than 25 cm. long.
Cone-scales prominently convex.
Leaves less than 7 cm. long 8. parviflora.
Leaves 9-12 cm. long 9. peuce.
Leaves 12-18 cm. long 10. excelsa.
Cone-scales thin, conforming to the surface of
the cone.
Cone relatively longer, its phyllotaxis 8/21 11. monticola.
Cone relatively shorter, its phyllotaxis 5/13 12. strobus.

6. PINUS AYACAHUITE

1838 P. ayacahuite Ehrenberg in Linnaea, xii. 492.
1848 P. strobiformis Engelmann in Wislizenus, Tour Mex. 102.
1857 P. Veitchii Roezl, Cat. Graines Conif. Mex. 32.
1858 P. Bonapartea Roezl in Gard. Chron. 358.
1858 P. Loudoniana Gordon, Pinet. 230.

Spring-shoots glabrous or pubescent. Leaves from 10 to 20 cm. long,
serrulate, their stomata ventral only, their resin-ducts external, often
numerous. Cones from 25 to 45 cm. long, pendent on long stalks,
subcylindrical or tapering, often curved; apophyses pale nut-brown, dull
or sublustrous, varying much in thickness, prolonged in various degrees,
the prolongations patulous, reflexed, recurved or revolute; seeds of
the southern typical form with a long wing, the wing diminishing and the
nut increasing in relative size northward.

The White Pine of Mexico and Guatemala grows on mountain-slopes and at
the head of ravines. It is not very hardy in cultivation except in the
milder parts of Great Britain and in northern Italy, where the forms
of central and northern Mexico have been very successful. The species
is best recognized by the prolonged apophyses of its large cone.

The variations in the size of the cone and in the prolongations of its
scales are many, but of far more significance is the remarkable
variation of the seed-wing, which is long in the southern part of the
range, short and broad in central Mexico, and rudimentary, like the
seed of P. flexilis, in the north. This makes it possible to establish
two well defined varieties--Veitchii and brachyptera. The three forms
of the species present a gradation from the long effective wing of the
Strobi to the rudimentary form of the Flexiles. Many of the seed-wings
of the var. Veitchii correspond, in their short broad form and opaque
coloring, with the characteristic wing of P. Lambertiana.

Plate X. (leaves and cones much reduced).

Fig. 103, Co