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64 MISSOURI BOTANICAL GARDEN BULLETIN 
Oncidium stipitatum Spathoglottis aureo-Vieillardii 
Ornithidium sophronitis Stanhopea bucephalus var. 
Ornithocephalus diceras guttata. 
Phalaenopsis Lueddemanniana Trichopilia marginata 
Pholidota chinensis Trigonidium Seemannii 
Polystachya panamensis Warscewiczella discolor 
Rodriguezia sp. Xylobium stachyobiorum 
Scaphyglottis prolifera 
THE MAIDENHAIR TREE 
The maidenhair tree (Ginkgo biloba) is the only survivor 
of an extensive family of plants of a prehistoric period. 
While it has been introduced into Europe and America from 
China and Japan, it is not known to be growing indigenous 
or in a wild state anywhere. 
It is a stately tree which at maturity reaches a height of 
100 feet, with a cylindric, slightly tapering trunk, usually 
slender when young, the branches becoming massive, ascend- 
ing or more or less spreading when older. The leaves are 
wedge-shaped, deciduous, resembling those of the maidenhair 
fern (Adiantum), striated on both sides with numerous par- 
allel veins, bright grass-green when young, dull rich green 
at maturity, and turning a clear bright yellow before they 
fall. The flowers are dioecious, the male catkins slender 
and stalked, the females on long footstalks, in pairs, of 
which generally only one persists. The fruit is a drupe, con- 
sisting of an acrid, ill-smelling pulp surrounding a smooth 
oval, cream-colored, thin-shelled nut with a sweet kernel. 
The fertilization of the flowers of this tree is unusual and 
interesting. The flowers appear in April or the beginning 
of May, and the pollen is distributed by the wind and set- 
tles on the tip of the female flower. Fertilization takes place 
in September, through the fusion of a motile male sperm 
from the pollen with an egg cell in the female flower. The 
development of the embryo takes place when the seed is full 
grown and ready to fall, sometimes even after the seed had 
already fallen to the ground. The offensive odor of the 
fleshy covering of the seed is caused by a fatty acid which 
is called ginkgoic acid. A full description of the ginkgo 
was given in the October, 1914, number of the BuLLETIN, 
