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FOXWORTHY. 
It is significant that Celebes, Borneo, Sumatra, J ava, and the Moluccas 
are the regions which have the largest number of species in common 
with the Islands, and there is not a single species common to the Phil- 
ippines and Formosa'. This certainly indicates that our G-ymnosperms 
have reached the Islands from the south and not from the north. . 
ECONOMIC IMPORTANCE. 
Cycadaceae. Cycas circinalis is used locally as a food plant, both the 
fruit and young leaves being used. Cycas revoluta is introduced and 
commonly cultivated as an ornamental. 
Taxaceae. The wood of some species may be used locally; but the 
species are mostly mountain forms, of infrequent occurrence and but 
little known. 
Pinaceae. AgatMs alba is of wide distribution in the mountains, and 
the resin is the Manila copal of commerce. It is extensively collected 
and exported. It is used locally for torches and medicinally, and is said 
to be one of the best preventives of leech bites. The pines furnish a 
supply of turpentine which is used locally. The wood of Pinus insularis 
is used in the northern part of the Island of Luzon; but the supply is 
not great enough to make it important as a commercial timber. 
Gnetaceae. Gnetum gnemon has very strong bast fibers in its cortex 
and is used locally for cordage. The young leaves are tender and are 
cooked .and eaten. G. latifolium also has very strong bast fibers and is 
similarly used. In some sections, the Negritos use the bark to make 
the strings for their bows. The fruit is edible and is generally eaten 
when cooked. 
TAXONOMY. 
The Gymnosperms are characterized by woody stems; vascular bun- 
dles of the axis arranged in a ring, a regular increase in thickness being 
in most cases effected by a closed cambium layer which produces phloem 
on the outer and xylem on the inner surface; embryo straight and 
embedded in endosperm; radicle developing a vigorous tap-root; flowers 
unisexual and (except Gnetacece) without perianth; microsporangia or 
pollen-sacs always borne on the under side Of the microsporangium ; 
ovulate scales not completely inclosed. 
CLASS I. CYCADALES. 
CYCADACEAE. 
Stem tall or short with internodes suppressed, usually unbranched, 
bearing a crown of large compound leaves. Dioecious. Pollen-sacs and 
ovules foliar, sporophylls not interspersed with sterile leaves, generally 
aggregated in terminal cones. Vascular bundles of stem collateral and 
