The Genus Pinus Part 20

=XIII. MACROCARPAE=

Pits of the ray-cells small. Wing-blade of the seed thick. Cones large.

Leaves long and stout.

This group is remarkable for the size of leaf, conelet, and cone. The peculiar thick seed-wing is more or less obscurely present among the species of the Insignes, but never attains the development that differentiates this group from all other Pines. The leaf-section is notable for the large amount of hypoderm and for the presence of both thick and thin outer walls of the endoderm-cells, both forms appearing in the same leaf.

Wing-blade with a short membranous extension.

Leaves in fascicles of 5 64. Torreyana Leaves in fascicles of 3 65. Sabiniana Wing-blade with a long membranous extension, leaves in fascicles of 3 66. Coulteri

64. PINUS TORREYANA

1855 P. Torreyana Parry ex Carriere, Trait. Conif. 326.

1860 P. lophosperma Lindley in Gard. Chron. 46.

Spring-shoots uninodal, pruinose. Leaves in fascicles of 5, from 20 to 33 cm. long, very stout; resin-ducts medial, hypoderm uniform or somewhat multiform and of many cells. Conelets large, mucronate. Cones from 10 to 15 cm. long, on stout peduncles, broad-ovate, symmetrical, somewhat persistent; apophyses chocolate-brown, prominently pyramidal, the umbo salient and capped with a small mucro; seed-wing short, very thick, the dorsal surface of the nut spotted with the black remnants of the spermoderm.

A tree 10 or 12 metres high, often semi-prostrate in exposed positions, confined to a restricted area on the coast north of San Diego, California, and to the Island of Santa Rosa. This species resembles P. Sabiniana in the length of its seed-wing and in the color of its cone, but is distinct in the short triangular umbo, in its pentamerous leaf-fascicles and in the mottled dorsal surface of its nut.

Plate x.x.xVIII.

Fig. 324, Cone and seed. Fig. 325, Magnified leaf-section.

65. PINUS SABINIANA

1833 P. Sabiniana Douglas in Trans. Linn. Soc. xvi. 747.

Spring-shoots multinodal, pruinose. Leaves in fascicles of 3, from 20 to 30 cm. long; resin-ducts medial, hypoderm multiform. Conelets large, their scales tapering to a sharp point. Cones from 15 to 25 cm. long, reflexed, ovate, slightly oblique, persistent; apophyses chocolate-brown, very prominent, the curved umbo confluent with the apophysis and with it forming a very large talon-like armature with a sharp apex and a broad thick base; seed-wing very thick, with a short membranous margin, the dorsal surface of the nut uniform in color.

A tree with spa.r.s.e gray-green foliage, growing in small groves on the foot-hills of the Sierra Nevada and Coast Ranges of California. Its three leaves and the uniform color of the nut distinguish it from P. Torreyana. From P. Coulteri it differs in the length of the membranous portion of the seed-wing and in its gray-green leaves.

Plate x.x.xVIII.

Fig. 326, Cone. Fig. 327, Seed, nut and wing. Fig. 328, Magnified leaf-section.

[Ill.u.s.tration: PLATE x.x.xVIII. P. TORREYANA (324, 325), SABINIANA (326-328)]

66. PINUS COULTERI

1837 P. Coulteri D. Don in Trans. Linn. Soc. xvii. 440.

1840 P. macrocarpa Lindley in Bot. Reg. xxvi. Misc. 62.

Spring-shoots multinodal, pruinose. Leaves in fascicles of 3, from 15 to 30 cm. long, very stout; resin-ducts medial, or with an occasional internal duct, hypoderm multiform and of many cells. Conelet very large, the scales tapering to a long sharp point. Cones from 25 to 35 cm. long, reflexed, ovate or oblong-ovate, somewhat oblique, persistent; apophyses subl.u.s.trous tawny yellow, very protuberant, with a narrow shoulder from which springs the umbo in the form of a large stout curved talon; seed-wing nearly equally divided between the very thick base and the membranous apex.

Remarkable among Pines for the size and weight of its cones, many times heavier than the longer cones of P. Lambertiana, ill.u.s.trating the great change that the cone-tissues undergo in the gradual evolution of the species. It is a tree with dark-green foliage, growing from northern Lower California over the mountains of southern California to the Santa Lucia range and to Mt. Diablo. It is of no value except for fuel and for its large nuts. It is best recognized by its seed. The cone differs from the others of this group in its yellow color, not unlike that of boxwood.

Plate x.x.xIX.

Fig. 329, Cone of small size. Fig. 330, Seed, nut and wing. Fig.

331, Magnified leaf-section. Fig. 332, Conelet.

[Ill.u.s.tration: PLATE x.x.xIX. PINUS COULTERI]