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Darwin, Charles, 1809-1882

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

The most important order is that of the Foraminifera.
RODENTS.--The gnawing Mammalia, such as the rats, rabbits, and squirrels.
They are especially characterised by the possession of a single pair of
chisel-like cutting teeth in each jaw, between which and the grinding teeth
there is a great gap.
RUBUS.--The bramble genus.
RUDIMENTARY.--Very imperfectly developed.
RUMINANTS.--The group of quadrupeds which ruminate or chew the cud, such as
oxen, sheep, and deer. They have divided hoofs, and are destitute of front
teeth in the upper jaw.
SACRAL.--Belonging to the sacrum, or the bone composed usually of two or
more united vertebrae to which the sides of the pelvis in vertebrate
animals are attached.
SARCODE.--The gelatinous material of which the bodies of the lowest animals
(Protozoa) are composed.
SCUTELLAE.--The horny plates with which the feet of birds are generally
more or less covered, especially in front.
SEDIMENTARY FORMATIONS.--Rocks deposited as sediments from water.
SEGMENTS.--The transverse rings of which the body of an articulate animal
or annelid is composed.
SEPALS.--The leaves or segments of the calyx, or outermost envelope of an
ordinary flower. They are usually green, but sometimes brightly coloured.
SERRATURES.--Teeth like those of a saw.
SESSILE.--Not supported on a stem or footstalk.
SILURIAN SYSTEM.--A very ancient system of fossiliferous rocks belonging to
the earlier part of the Palaeozoic series.


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