SPALACIDÆ, OR MOLE RATS--Characteristics of the Family--Habits--Food--THE MOLE RAT--Distribution--Description--THE CHESTNUT MOLE RAT--THE NAKED MOLE RAT--THE STRAND MOLE RAT--Description--Habits--THE CAPE MOLE RAT--GEOMYIDÆ, OR POUCHED RATS--Characteristics of the Family--The Cheek-pouches--THE COMMON POCKET GOPHER--Distribution--Description--Burrowing--Runs--Subterranean Dwelling--THE NORTHERN POCKET GOPHER--HETEROMYINÆ, OR POUCHED MICE--Difficulties as to Position--Characteristics--PHILLIPS’ POCKET MOUSE--Where Found--Description--THE YELLOW POCKET MOUSE--THE LEAST POCKET MOUSE--DIPODIDÆ, OR JERBOAS--Organisation for Jumping--Characteristics--Distribution--THE AMERICAN JUMPING MOUSE--Description--Characters peculiar to itself--Habits--THE TRUE JERBOAS--Characters--THE JERBOA--Distribution--Habits--Mode of Locomotion--THE ALACTAGA--THE CAPE JUMPING HARE--THE PORCUPINE-LIKE RODENTS--OCTODONTIDÆ--Characteristics--Sub-Family CTENODACTYLINÆ--THE GUNDI--THE DEGU--Description--Habits--THE BROWN SCHIZODON--THE TUKOTUKO--THE CURURO--THE ROCK RAT--Sub-Family, ECHINOMYINÆ--THE COYPU--One of the Largest Rodents--Description--Burrows--Habits--Mother and Young--THE HUTIA CONGA--THE HUTIA CARABALI--THE GROUND RAT 120 CHAPTER IV. PORCUPINES--CHINCHILLAS--AGOUTIS--CAVIES--HARES AND RABBITS--PIKAS. HYSTRICIDÆ, THE PORCUPINES--Conversion of Hairs into Spines--Skull--Dentition--Tail--Sub-families--The True Porcupines--The Tree Porcupines--THE COMMON PORCUPINE--Distribution--Description--The Crest of Bristles--Nature of the Spines--Habits--Young--Flesh--On the Defensive--Other Species--Species of Tree Porcupines--THE COUENDOU--THE COUIY--Description--Habits--THE URSON, OR CANADA PORCUPINE--Description--Habits--Food--CHINCHILLIDÆ, THE CHINCHILLAS--Characteristics--THE VISCACHA--Description--Life on the Pampas--Their Burrows--Habits--The Chinchillas of the Andes--THE CHINCHILLA--THE SHORT-TAILED CHINCHILLA--CUVIER’S CHINCHILLA--THE PALE-FOOTED CHINCHILLA--DASYPROCTIDÆ, THE AGOUTIS--Characters--THE AGOUTI--Distribution--Appearance--Habits--AZARA’S AGOUTI--THE ACOUCHY--THE PACA--Appearance--Distribution--Habits--DINOMYIDÆ--Founded for a Single Species--Description--Rarity--CAVIIDÆ, THE CAVIES--Characteristics--THE RESTLESS CAVY--Appearance--Habits--The Guinea-Pig Controversy--THE BOLIVIAN CAVY--THE ROCK CAVY--THE SOUTHERN CAVY--THE PATAGONIAN CAVY, OR MARA--Peculiar Features--Its Burrows--Mode of Running--THE CAPYBARA--Its Teeth--Where Found--Habits--THE DOUBLE-TOOTHED RODENTS--Characteristics--LEPORIDÆ, THE HARES AND RABBITS--Structural Peculiarities--Distribution--Disposition--THE COMMON HARE--Hind Legs--Speed--Its “Doubles”--Other Artifices--Its “Form”--Habits--Food--Pet Hares--THE RABBIT--Distribution--Habits--Domesticated--THE MOUNTAIN HARE--LAGOMYIDÆ, THE PIKAS--Characteristics--Distribution--THE ALPINE PIKA--THE