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Darwin, Charles, 1809-1882

"The Origin of Species by means of Natural Selection, 6th Edition"

--The minute bud between the seed-leaves of
newly-germinated plants.
PLUTONIC ROCKS.--Rocks supposed to have been produced by igneous action in
the depths of the earth.
POLLEN.--The male element in flowering plants; usually a fine dust produced
by the anthers, which, by contact with the stigma effects the fecundation
of the seeds. This impregnation is brought about by means of tubes
(POLLEN-TUBES) which issue from the pollen-grains adhering to the stigma,
and penetrate through the tissues until they reach the ovary.
POLYANDROUS (flowers).--Flowers having many stamens.
POLYGAMOUS PLANTS.--Plants in which some flowers are unisexual and others
hermaphrodite. The unisexual (male and female) flowers, may be on the same
or on different plants.
POLYMORPHIC.--Presenting many forms.
POLYZOARY.--The common structure formed by the cells of the Polyzoa, such
as the well-known seamats.
PREHENSILE.--Capable of grasping.
PREPOTENT.--Having a superiority of power.
PRIMARIES.--The feathers forming the tip of the wing of a bird, and
inserted upon that part which represents the hand of man.
PROCESSES.--Projecting portions of bones, usually for the attachment of
muscles, ligaments, etc.
PROPOLIS.--A resinous material collected by the hivebees from the opening
buds of various trees.
PROTEAN.--Exceedingly variable.
PROTOZOA.--The lowest great division of the animal kingdom.


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