Chapter V: Introduction: The Squirrel, Marmot, Anomalure, Haplodont, and

BEAVER FAMILIES.

Character of the Order--A well-defined Group--Teeth
Evidence--Kinds and Number of Teeth--The Incisors: their
Growth, Renewal, and Composition--The Molars--The Gnawing
Process--Skeleton--Brain--Senses--Body--Insectivora
and Rodentia--Food of Rodents--Classification--THE
SIMPLE-TOOTHED RODENTS--Characteristics--THE SQUIRREL-LIKE
RODENTS--SCIURIDÆ--Distinctive Features--THE
COMMON SQUIRREL--Form--Distribution--Food--Bad
Qualities--Habits--THE GREY SQUIRREL--THE FOX
SQUIRREL--Flying Squirrels--Their Parachute Membrane--THE
TAGUAN--Appearance--Habits--Other Species--THE
POLATOUCHE--THE ASSAPAN--The Genus _Xerus_--THE GROUND
SQUIRRELS--THE COMMON CHIPMUNK--THE MARMOTS--Distinguishing
Features--THE SPERMOPHILES--THE GOPHER--THE SISEL,
OR SUSLIK--THE BARKING SQUIRRELS--THE PRAIRIE
DOG--Description--Species--Habits--Burrows--Fellow-inmates
in their “Villages”--THE TRUE MARMOTS--THE BOBAC--THE
ALPINE MARMOT--THE WOODCHUCK--THE HOARY MARMOT, OR
WHISTLER--ANOMALURIDÆ--Tail Peculiarity--Distinctive
Features--HAPLODONTIDÆ--Description--THE
SEWELLEL--CASTORIDÆ--THE BEAVER--Skeletal
Peculiarities--General Form--Appearance--Distribution--The
Beavers of the Old and New World--Habits--Wonderful
Sagacity--The Building Instinct--Their Method of Working--The
various Stages--Their Lodges--Their Dams--Activity by
Night--Flesh--Hunted--The _Castoreum_ 81