th
smooth walls.

All the species of this section, except P. Nelsonii, have deciduous
fascicle-sheaths. There are but two species of Diploxylon with
deciduous sheaths, P. leiophylla and P. Lumholtzii, both of them
easily recognized. The deciduous sheath, therefore, is an obvious and
useful means for recognizing the Soft Pines. On the characters of the
fruit and the wood Haploxylon can be divided into two subsections.

a. Cembra Umbo of the cone-scale terminal.
b. Paracembra Umbo of the cone-scale dorsal.

=Cembra=

Umbo of the cone-scale terminal. Scales of the conelet unarmed. Leaves
in fascicles of 5, the sheath deciduous, the two dermal tissues
distinct, the hypoderm-cells uniform. Pits of the cells of the wood-rays
large.

Seeds wingless.
Cones indehiscent I. Cembrae.
Cones dehiscent II. Flexiles.
Seeds with an adnate wing III. Strobi.

=I. CEMBRAE=

Seeds wingless. Cones indehiscent, deciduous at maturity.

In this group of species there is no segregation of sclerenchyma into
an effective tissue. The cones are inert under hygrometric changes and
may always be recognized in herbaria by their persistent occlusion and
soft tissues. The seeds are released only by the disintegration of the
fallen cone. There is, however, a vicarious dissemination by predatory
crows (genus Nucifraga) and rodents.

Leaves serrulate, their stomata ventral only.
Cones relatively larger, the apophyses protuberant 1. koraiensis.
Cones relatively smaller, the apophyses appressed 2. cembra.
Leaves entire, their stomata ventral and dorsal 3. albicaulis.

1. PINUS KORAIENSIS

1784 P. strobus Thunberg, Fl. Jap. 275 (not Linnaeus).
1842 P. koraiensis Siebold & Zuccarini, Fl. Jap. ii. 38.
1857 P. mandschurica Ruprecht in Bull. Acad. Sci. St. Petersb. xv. 382.

Spring-shoots more or less densely tomentose. Leaves from 8 to 12 cm.
long, serrulate, stomata ventral only, resin-ducts medial and confined
to the angles. Conelets large, subterminal, or on young trees often
pseudolateral. Cones indehiscent, from 9 to 14 cm. long,
short-pedunculate, ovoid-conical or subcylindrical; apophyses dull pale
nut-brown, rugose, shrinking much in drying and exposing the seeds,
prolonged and tapering to a more or less reflexed tip, the umbo
inconspicuous; seeds large, wingless, the spermoderm entire.

A species of