ntana
Resin-ducts mostly medial.
Bark-formation late 31. luchuensis
Bark-formation early.
Cone nut-brown 32. Thunbergii
Cone lustrous tawny yellow 33. nigra
Cones narrow cylindrical 34. Merkusii
Cones tenaciously persistent.
Leaves stout, relatively short 35. sinensis
Leaves slender, relatively long 36. insularis

25. PINUS RESINOSA

1789 P. resinosa Aiton, Hort. Kew. iii. 367.
1810 P. rubra Michaux f. Hist. Arbr. Am. i. 45, t. 1.

Spring-shoots uninodal. Leaves binate, from 12 to 17 cm. long;
resin-ducts external or external and medial; hypoderm uniform and
inconspicuous. Scales of the conelet mutic. Cones from 4 to 6 cm. long,
subsessile, symmetrical, deciduous the third year, leaving a few basal
scales on the tree; apophyses sublustrous, nut-brown, somewhat thickened
along a transverse keel.

From Nova Scotia and Lake St. John this species ranges westward to the
Winnipeg River and southward into Minnesota, Michigan, northern New
York and eastern Massachusetts, with rare occurrence on the mountains
of Pennsylvania. Under cultivation it is a beautiful tree, adapted to
cold-temperate climates. It was considered by Loiseleur (1812) and by
Spach (1842) to be a variety of P. nigra (laricio). The two species
vary in the color of the cone, the anatomy of the leaves, the buds,
and in the armature of the conelet. A fallen cone of this species is
moreover usually imperfect from the loss of a few basal scales.

Plate XIX.

Fig. 170, Cone and enlarged conelet. Fig. 171, Leaf-fascicle and
magnified leaf-section.

26. PINUS TROPICALIS

1851 P. tropicalis Morelet in Rev. Hort. Cote d'Or, i. 105.
1904 P. terthrocarpa Shaw in Gard. Chron. ser. 3, xxxv. 179, f. 74.

Spring-shoots uninodal. Leaves binate, sometimes ternate, from 15 to 30
cm. long, rigid, erect; hypoderm of uniform thick-walled cells;
resin-ducts of remarkable size, septal, or not quite touching the
endoderm and technically external. Scales of the conelet minutely
tuberculate. Cones from 5 to 8 cm. long, short-pedunculate, erect or
patulous; ovate-conic, symmetrical; apophyses rufous brown,
low-pyramidal, the umbo mutic.

Growing at sea-level within the tropics and confined to western Cuba
and the Isle of Pines. On the islan