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THE

CONCISE

KNOWLEDGE

LIBRART



NATURAL HISTORY



THE CONCISE KNOWLEDGE LIBRARY



NATURAL HISTORY



BY



R. LYDEKKER,

B.A., F. R. S., V.P. G. S.

W. F. KIRBY,

F. L. S., F. E. S.

B. B. WOODWARD,

F. L. S., F. G. S.

R. KIRKPATRICK,
R. I. POCOCK,



R. BOWDLER SHARPE,

LL.D.

W. GARSTANG,

M.A., F. Z. S.

F. A. BATHER,

M.A., F.G. S.

H. M. BERNARD,

M. A., F. L. S.




NEW YORK
D. APPLETON AND COMPANY

1897



HOLOGY LBBfcAB*

Authorized Edition.

(SIFT



BIOLOGV



PREFACE

THIS work aims to be a concise and popular Natural
History, at once accurate in statement, handy in form,
and ready of reference.

The several departments of Zoological science are
treated by specialists, all of whom are distinguished as
authorities and as original investigators ; and the text
is illustrated by upwards of five hundred original draw-
ings made and reproduced expressly for the work.

A concise systematic index precedes the work,
and a full alphabetical index which contains about ten
thousand references is given at the end. Great pains
have been taken to render these both accurate and
complete.



M710175



TABLE OF AUTHORS



MAMMALIA (Mammals)
AVES (Birds} -
REPTILIA (Reptiles] -
AMPHIBIA (Frogs, Toads, &*c.)
PISCES (Fishes)

CYCLOSTOMATA (Lampreys, &c.}
PROTOCHORDA (Lancelet, &*c.)
HEMICHORDA (Balanoglossus}
ARTHROPOD A (Insects, &*.) -
MoLLUacA (Snails, &c?)
BRACHIOPODA (Lamp Shells, &c.
ECHINODERMA (Star Fish, &c.)
BRYOZOA (Moss Animals}
VERMES (Worms)

COELENTERA (Corals,

PROTOZOA (Animalcules)



R. LYDEKKER, F.R.S., V.P.G.S., &c.
R. BOWDLER SHARPE, LL.D., &c.
R. LYDEKKER, F.R.S., V.P.G.S., &c.
R. LYDEKKER, F.R.S., V.P.G.S., &c.
R. LYDEKKER, F.R.S., V.P.G.S., &c.
R. LYDEKKER, F.R.S., V.P.G.S., &c.
W. GARSTANG, M.A., F.Z.S., &c.
W. GARSTANG, M.A., F.Z.S., &c.
W. F. KIRBY, F.L.S., F.E.S , &c.
B. B. WOODWARD, F.L.S., F.G.S., &c.
F. A. BATHER, M.A., F.G.S., &c.
F. A. BATHER, M.A., F.G.S., &c.
R. KlRKPATRlCK (British Museum).
R. I. POCOCK (British Museum).
H. M. BERNARD, M.A., F.L.S., &c.
H. M. BERNARD, M.A., F.L.S., &c.



THE ANIMAL KINGDOM.



SUB-KINGDOM L VERTEBRATA.



CLASS I. MAMMALIA.



CHARACTERISTICS of Vertebra* es
Distinctive Features of Mammals
Geographical Distribution
Order I. Primates.

Apes, Monkeys, and Lemurs ..
Ord.r II. Chiroptera.

^ The Bats

Order III. Insectivora.

Insect-eating Mammals .
Order IV. Carnivora.

Flesh-eating Mammals ...
Order V. Rodentia.

Mammals that Gnaw ...



MAMMALS.

Page
I
2

7



10

33
42
50



Page
118



Order VI. Ungulata.

'1 he Hoofed Mammals ...
Order VII. Sirenia.

The Manatis and Dugongs ... 165
Order VIII. Cetacea.

Whales Porpoises, and Dolphins 169
Order IX. Kdentata.

S!o hs, Ant-eaters, and Armadillos 181
Or :er X. Effodientia.

Aard-varks and Pangolins ... 188
Order XL Marsupialia.

Pouched Mammals 190

Order XII. Monotremata.

Egg-laying Mammals 214



CLASS II. AVES.



Bird Structure and Development

SUB-CLASS SAURUR^E.

Order Archseopteryges.
The Archseopteryx

SUB-CLASS RATIT^E.

Order Rheiformes.

The Rheas :

Order Struthioniformes.

The Ostriches

Order Casuariiformes.

The Emus and Cassowaries
Order Dinornithiformes, Lie.

The Extinct Moas
Order Apterygiformes.

The Apteryges ...



B1K
218

220

221
222

223
22 4
22 4


DS.

CARINATE BIRDS.

Order Tin ami formes.
The Tinamous
Order Gall i formes.
The Game-birds
Order Pterocletes.
The Sand-grouse
Order Columbiformes.
Pigeons . .


... 225
... 2-6
... 241

2A2


Sub-order Didi,
The Dodo, Etc,
Order Opisthocomiformes.
The Hoatzini
Order Ralliformes.
The Rails
Order Podicipedidiformes.
The Grebes


... 245
... 247
... 248
... 253



IX



SYSTEMATIC INDEX.





Page


Pa 3 e


B I KDS continued.








Order Colymbiformes.




Order Phoenicopteriformes.




The Divers


254


The F'amingoes ...


... 283


Order Sphenisciformes.




Sub-order Pa'amedeae.




The Penguins ...


255


The Screamers ...


... 290


Order Procellariiformes.




Order Anseriformes.




The Petrels


256


Geese, Etc.


... 290


Order Alciformes.




Sub-order Anseres.




The Auks


259


Ducks, Etc


... 292


Order Lariformes.




Order Pelecaniformes.




The Gulls


26l


The Pelicans, Etc.


... 298


Order Charadriiformes.




Sub-order Sulae.




The Plovers and Bustards


264


The Gannets


... 299


Sub-order Attagides.




Sub-order Phalacrocoraces.




The Seed-snipes ...


266


The Cormorants ...


... 299


Sub-order Charadrii.




Sub-order Pelecani.




The Plovers


266


The Pelicans


... 301


Sub-order Glareolse.




Sub-order Fregati.




The Pratincoles


272


The Frigate Birds


33


Sub-order Cursorii.




Order Cathartidiformes.




The Coursers


272


The Turkey Vultures ..


54


Sub-order OZdicnemi.




Order Accipitriformes.




The Stone- plovers


273


Birds of Prey


... 304


Sub-order Otides.




Sub-order Serpentarii.




The Bustards


273


The Secretary Birds


35


Order Grui formes.




Sub-order Accipitres.




The Cranes


274


The True Birds of Prey...


35


Sub-order Grues.




Sub-order Pandiones.




The True Cranes


274


The Ospreys


... 320


Sub-order Arami.




Sub-order Striges.




The Liinpkins


275


The Owls


... 320


Sub-order Rhinochetides.




Order Psittaciformes.




The Kagus


276


The Parrots


... 325


Sub-order Mesitides.




Order Coracii formes.




The Madagascar Kagus


276


r lhe Picarian Birds


332


Sub-order Eurypygse.




Sub-order Steatornithes.




The Sun-bitterns


276


The Oil-birds


332


Sub-order Psophise.




Sub-order Podargi.




The Trumpeters


277


The Frog-mouths


333


Sub-order Dicholophi.




Sub-order Leptosomati.




The Seriamas


277


The Kiroumbos ...


335


Order Stereornithes.




Sub- order Coraciae.




The Extinct Birds of Patagonia


2 7 8


The Rollers


335


Order Ardeiformes.




Sub-order Halcyones.




The Herons, Etc.


2 7 8


The King-fishers


... 336


Sub-order Ciconii.




Sub-order Bucerotes.




The Storks


2 7 8


The Hornbills ...


339


Sub-order Scopi.




Sub-order Upupge.




Hammer-headed Storks


28l


The Hoopoes


... 340


Sub-order Balaenicipitide-.




Sub -order Meropes.




Shoe-billed Storks


2?2


The Bee-eateis


... 340


Sub-order Herodiones.




Sub-order Momoti.




The Herons


282


The Motmots


- 341


Sub-order Platalese.




Sub-order Todi.




The Spoon-bills, Etc. ...


286


The Todies


... 342



MAMMALS.



xi





Page


Page


BIRD s con tin ued.








Sub-order Caprimulgi.




Sub order Rhamphastides.




The Nightjars


... 342


The Toucans


- 352


Sub-order Cypseli.




Sub-order Capitones.




The Swifts


345


The Barbels


352


Sub-order Trochili.




Sub-order Indicatores.




The Humming-birds


.. 347


The Honey-guides


... 353


Sub-order Colii.




Order Piciformes.




The Colics


... 348


Woodpecker-like Birds ...


- 353


Order Trogones.




Sub-order Pici.




The Trogons


349


The Woodpeckers


... 353


Order Coccyges.




Sub-order Buccones.




Cuckoo-like Birds


... 349


The Puff-birds


- 355


Sub-order Cuculi.




Order Eurylsemi.




The Cuckoos


349


The Broad-bills


... 356


Sub-order Musophagi.




Order Passeriformes.




The Touracoes ...


351


The Perching Birds


.- 357


Order Scansores.








The Climbing Birds


35 2







CLASS III. REPTILIA.



REPTILES.



Characteristics of Reptiles
Classification of Reptiles .. . ....

Order I. Crocodilia.

Crocodiles, Alligators, Garials ..,
Order II. Chelonia.

Tortoises and Turtles ... ...

Sub-order i. Cryptodira.

Land Tortoises, Etc. ...
Sub-order ii. Pleurodira.

Fresh- water Tortoises ...
Sub-order iii. Trionychoidea.

The Soft Tortoises



377
378.

378
383
385
392
394



Order III. Sqnamata.

Scaled Reptiles 395

Sub-order i. Lacertilia.

The Lizards ... ... ... 396

Sub-order ii. Rhiptoglossa.

The Chamseleons ... ... 411

Sub-order iii. Ophidia.

The Snakes ... ... ... 412

Order IV. Rhynchocephalia.

The Tuaiera 429



CLASS IV. AMPHIBIA.
AMPHIBIANS.



Characteristics of Amphibians ... 431
Order I. Ecaudata.

Frogs and Toads 435

Sub-order i. Finnisternia.

Typical Frogs, Etc 436

Sub-order ii. Arcifera.

The Toads, Etc 440



Sub-order iii. Aglossa. .

The Surinam Water-toad, Etc. 444
Order II. Caudata.

Newts and Salamanders ... 445

Order III. Apoda.

The Csecilians 453



xii



S YSTEMA TIC INDEX.



CLASS V. PISCES.
FISHES.



Page
456
458



Characteristics of Fishes ...
The Classification of Fishes

SUB-CLASS I. DIPNOI.

Lung-fishes 459

SUB-CLASS II. HOLOCEPHALI.
The Chimaeroids ... ... ... 461

SUB-CLASS III. TELEOSTOMI.

Bony Fishes and Ganoids 462

Order I. Actinopterygii.

The Fan-finned Teleostomes ... 463
Sub-order i. Acanthopterygii.

The Spiny-finned Fishes, Etc. ... 463
Section Perciformes.

The Common Perch, Etc. ... 463
Section Scorpseni formes.

The Micropus, Etc. ... ... 467

Section Berychiformes.

The Slime-heads 467

Section Curtiformes.

The Indian Curtis, Etc. ... 468

Section Polynemiformes.

The Poly nemus, Etc 468

Section Sciaeniformes.

The Meagre, Etc 468

Section Xiphiiformes.

The Sword-fish ... 469

Section Trichiuriformes.

The Scabbard Fish, Etc. ... 470

Section Cotto-Scombriformes.

The Surgeons, Etc. ... ... 470

Section Gobiiformes.

The Lump-suckers, Etc. ... 476

Section Blenniiformes.

Marine Band-fishes, Etc. ... 477

Section Mugiliformes.

The Barracuda-pikes, Etc. ... 478
Section Scombresociformes.

The Flying-fish, Etc. ... ... 479

Section Gastmsteiformes.

The Sticklebacks, Etc 480

Section Centrisciforme?.

The Bellows-fish, Etc. 482

Section Gobioesociformes.

The Sucker-fishes, Etc. ... ... 482

Section Channiformes.

The Serpent-heads, Etc. ... 482



Page
Section Labyrinthici.

The Climbing-perch, Etc. ... 483
Section Lophotiformes.

The Unicorn-fish ... ... 484

Section Tseniiformes.

The Riband- fishes 484

Section Notacanthiformes.

The Thorn-backs ... ... 485

Section Pharyngognathi.

The Coral-fishes, Etc 485

Sub-order ii. Lophobranchii.

The Pipe-fishes, Etc 487

Sub-order hi. Plectognathi.

The Spine-clad Globe-fishes ... 488
Sub-order iv. Anacanlhini.

The Common Cod, Etc. ... 490

Sub-order v. Physostomi. ... 493

Section A. Apodes.

The Eel-tribe 493

Section B. Nematognathi.

The Cat-fishes 496

Section C. Plectispondyli.

The Common Carp, Etc. ... 497

Section D. Haplopomi.

The Common Pike, Etc. ... 501

Section E. Scyphophori.

The Gymnarchus, Etc. ... ... 53

Section F. Isospondyli.

The Salmon, Etc. 503

Sub-order vi. ^Etheospondsli.

The Bony Pikes, Etc ... 509
Sub-order vii. Protosp ndyli.

The Bow-fin 510

Sub-order viii. Chondrostei.

The Sturgeons 510

Order II. Crossopterygii.

Fringe-finned Ganoids 512

SUB-CLASS IV. ELASMOBRANCHII.

Sharks and Rays ... 513

Order Selachii.

Sharks, Dog-fishes, Etc. ... 515

Sub-order i. Asterospondyli.

The Blue Shark, Etc 515

Sub-order ii. Tectospond\ li.

The Saw-fish ... .'.. ... 519



ARTHKOPODA,



xiii



CLASS VI. CYCLOSTOMA.
LAMPREYS AND HAG-FISHES.



Characteristics of Cyclostoma



Page I
523 I Lampreys and Hag-fishes ...



Page
5 2 4



CLASS VII. PROTOCHORDA.



SUB-CLASS I. CEPHALOCHORDA. SUB-CLASS II. UROCHORDA.

The Lancelet ... ... ... 526 J The Common Sea-squirt, Etc. ... 527



CLASS VIII. HEMICHORDA.

Hemichorda or Enteropneusta ... 528 | The Balanoglossus ...



SUB-KINGDOM II. ARTHROPODA.



CRUSTACEA, INSECT A,



CLASS I. CRUSTACEA.



Characteristics of Arthropoda ... 529
Edible Arthropoda, Etc. ... ... 530

SUB-CLASS I. ENTOMOSTRACA.

The Smaller Crustacea 531

Order I. Phyllopoda.

The Water-flea, Etc 531

Order II. Ostracoda.

The Ostracoda 532

Order III. Copepoda.

The Cyclops, Carp-lice, Etc. ... 532
Order IV. Cirripedia.

Barnacles, Etc. ... ... ... 533

SUB-CLASS II. MALACOSTRACA.

The Higher Crustacea 533

Order L Arthrostraca.
Sub-order i. Isopoda.

Wood-lice, Etc 534

Sub-order ii. Amphipoda.

The whale-louse, Etc 534



Order II. Thoracostraca.
Sub-order i. Cumacea.

Marine Parasites, Etc. ... .. 535

Sub-order ii. Stomatopoda.

Squilla Mantis, Etc. ... ... 535

Sub-order iii. Schizopoda.

Shrimp-like Crustacea 536

Order III. Decapoda.
Sub-order i. Macrura.

Shrimps, Lobsters, Crayfish, Etc. 536
Sub-order ii. Anomura.

Robber Crabs, Hermit Crabs, Etc. 537
Sub-order iii. Brachyura.

The Spicier Crab, Etc. ... ... 537

SUB-CLASS III. GIGANTOSTRACA.
Order Xiphosura.

The King-crabs 538

SUB-CLASS IV. PYCNOGONIDA.
Order Pycnogonida ... ... 539



CLASS II. ARACHNIDA.
SPIDERS, SCORPIONS, AND MITES.



Order I. Scorpionidea.
The Scorpions, Etc.



540



Order II. Solpugidea.
Galeodes Arabs, Etc.



541



SYSTEMATIC INDEX.



ARACHNIDA continued.
Order III. Pseudoscorpionidea.

Book-scorpions

Order IV. Pedipalpi.

False Scorpions ...
Order V. Phalangiida.

Harvest-men, Etc.
Order VI. Araneida.

Spiders ...



Page



541

54i



542



Order VII. Acarina.

Mites and Ticks ..
Order VIII. Tardigrada.

Moss Mites, Etc.
Order IX. Linguatulida.

Worm-like Parasites



CLASS III. MYRIOPODA.
CENTIPEDES AND MILLEPEDES.



Order Chilopoda.
Centipedes



548



Order Chilognatha.
Millepedes



CLASS IV. PROTRACIIEATA.
Order Pcripatidse 550 | Peripatus luliformis



Page

545
547
548



549



CLASS V.-

Classification of Insects 551
Order Coleoptera.
Beetles c c i


-INSECTA.

Order Lepidoptera.
Butterflies and Moths ... ...
Order Hemiptera.
Bugs and Frog-hoppers...
Sub-order Heteroptera.
Bugs, Etc.
Sub-order Homoptera.
Frog-hoppers, Plant-lice, Etc. ...
Order Anoplura.
The True Lice
Order Diptera.
The Flies...


Order Orthoptera.
Crickets, Locusts, Etc....
Order Neuroptera.
Lace-winged Insects
Order Trichoptera.
Caddis Flies, Etc.
Order Hymenoptera.
Bees, Wasps Ants, Etc.


... 562
... 568
... 572

573



581

594
595
598
602
602



SUB-KINGDOM III. MOLLUSCA.

WHELKS, OYSTERS, SNAILS, &c.
CLASS I. AMPHINEURA.



Characteristics of Mollusca ... 610

Classification of Mollusca ... 615

Order I. Polyplacophora.

Chitons, Etc 615



Order II. Aplacophora.

(Worm -like Mollusca) 616

Sub-order i. Neomeniina.

Neomenians ... ... ... 616

Sub-order ii. Choetodermatina.



MOLL USCABRACHIOPODA .



CLASS II. PELECV

Page

Characteristics of the Pelecypoda... 616
Order I. Protobranchiata.

Nutshells, Etc 620

Order II. Filibranchiata.
Sub-order i. Anomiaceae.

The Saddle Oyster, Etc. ... 621

Sub-order ii. Arcacea.

Noah's Ark Shells, Etc. ... 621

Sub-order iii-. Trigoniacea.

The Trigonia 621

Sub-order iv. Mytilacea.

The Marine Mussel, Etc. ... 621

Order III. Pseudolamellibranchiata.

The Oyster, Etc. 622

Sub-order i. Aviculacea.

Swallow Shells, Etc 622

Sub-order ii. Ostreacea.

Oysters ... ... ... ... 622



PODA (BIVALVES}.



Page



Sub-order iii. Pectinacea.

Scallops, Etc. ... ... ... 622

Order IV. Eulamellibranchiata.
Sub-order i. Submytilacea.

Fresh- water Mussels ... ... 623

Sub-order ii. Tellinacea.

Sunset Shells, Etc. ... ... 624

Sub-order iii. Veneracea.

The Venus Shells, Etc 625

Sub-order iv. Cardiacea.

The Cockles, Etc. ... ... 625

Sub-order v. Myacea.

The Mya or Gaper, Etc. ... 626

Sub-order vi. Pholadacea.

The Piddock and Ship-worm, Etc. 627
Sub-order vii. Anatinacea.

Pandora, Etc. ... ... ... 627

Order V. Septibranchiata.

Poromyidae, Etc. .., ... 628



CLASS III. SCAPHOPODA.

Scaphopoda or Solenoconcha ... 628 | The Elephant's-tooth Shells



628



CLASS IV. <

SUB-CLASS A. STREPTONEURA.
Order I. Scutibranchiata.

The Limpets, Etc.
Sub-order i. Docoglossa.

The Common Limpet, Etc.
Sub-order ii. Rhipidoglossa.

The Keyhole Limpet, Etc.
Order II. Pectinibranchia'.a.

(The Marine Gastropods)
Sub-order i. Gymnoglossa.

(Parasitic Mollusca)
Sub-order ii. Ptenoglossa.

The Purple Sea-snails, Etc.
Sub-order iii. Taenioglossa.

The Cowries, Etc.
Sub-order iv. Rachiglossa.

The Dog-periwinkle, Etc.



631
631
631

032

633
633
633



637



GASTROPODA.

Sub-order v. Toxoglossa.

The Cone Shells, Etc 638

SUB-CLASS B.- EUTHYNEURA.
Order I. Opisthobranchiata.
Sub-order i. Tectibranchiata.
Group A. Bulloidea.

The Bulla, Etc 640

Group B. Aplysioidea.

The Sea-hares, Etc. ... ... 640

Group C. Pleurobranchoidea.
Sub-or>!er ii. Nudibranchiata.

The Sei-slugs .. ... ... 640

Order II. Pulmonata.

Land Mollusca ... ... ... 641

Sub-order i. Basommatophora.

Pond-snails, Etc. ... ... 641

Sub-order ii. Stylommatophora.

Land-snails, Eic.



CLASS V. CEPHALOPODA.



Order I. Tetrabranchiata.

The Nautilus ,

Order II. Dibranchiata.



6 45



| Sub- order i. Dec i pod a.

The Cuttle-fish, Etc.

Sub-order ii. Octopoda.

The Argonaut, Etc.



SUB-KINGDOM IV. BRACHIOPODA.

LAMPSHELLS, &c.
Characteristics of Brachiopods ... 649 | Lampshells, Etc. ...



642

646
647

649



SYSTEMATIC INDEX.



SUB-KINGDOM V. ECHINODERMA.

STAR-FISH, SEA-URCHINS, &c.

Page Page

Characteristics of Echinoderma ... 6,3
Class Asteroidea.

Star-fish 656

Class Ophiuroidea.

Brittle-stars, lite. 658



Clas> Echinoidea.

Sea-.urchins
Class Holothuroidea.

Sea-cucumbers
Class (_ rinoidea.

Sea-lilies 662



659
660



SUB-KINGDOM



VI. BRYOZOA [POLYZOA].

MOSS ANIMALS.



SUB-CLASS I. INFUNDII;ULAT.\.
Order Chilostomata.

Lip-mouthed Bryozoa ... ... 665

Order Cyclostomata.

Circular-mouthed Bryozoa ... 668



SUB-KIN

Characteristics of Worms ...
Class Annelida.

The Ringed Worms, Etc.
Sub-class Chaetopoda.

Bristle-footed Worms
Order Polychseta.

Marine Worms

Sub-order Sedentaria.

Tube-making Worms
Sub-order Errantia.

The Predacious Sea-worms
Order Oligochaeta.

The Earth-worms, Etc. ...
Sub-class Hirudinea.

The Leeches



Order Ctenostomata.
Comb-mouthed Bryozoa



GDOM VII. VERMES.

THE WORMS.
... 670 Class Gephyrea.

The Gephyrein Worms.,
... 671 Class Nematohelminthes.

The Thread- worms
... 671 Class Rotifera.

The Wheel-animalcules .
... 671 Class Nemtrtmea.

Nemertine Wo ms
... 672 Class Platyhelminthes.

The Flat- worms ...
Etc. 672 Sub-class Turbellarin.

The Phnarian Worms .
674 Sub-class Cestocla.

The Tape-worms
... 675 Sub-class Tremaioda.

The Fluke-worms



SUB-KINGDOM VIII. COELENTERA.

SPONGES, CORALS, &c.
Characteristics of Coelentera ... 690 Section i. The Hydrozoa.

Group I. Porifera. The Zoophytes, Etc.

The Sponges ... ... ... 690 | Section ii. The Scyphozoa.

Group II. The Cnidaria. Sea-anemones and Corals

The Stinging Coelenterates ... 694 ; Section iii. Ctenophora.

The Comb-bearers



SUB-KINGDOM IX. PROTOZOA.

ANIMALCULE.

713 : Section iii. The Heliozoa

713 ! Section iv. The Radiolaria

7H

714

715



Characteristics of Protozoa
Group I. The Monera ...
Group II. The Rhizopoda
Section i. The Amoeba ...
Section ii. The Foraminiiera



Group III. The Flagellata
Group IV. The Grrgnrinae
Group V. The Infusoria



668



SUB-CLASS II. LOPHOPODA.
Fiesh- water Bryozoa, Etc. ... 668



... 677

... 678

... 682

... 683

... 685

... 685

... 686

, 688



694
700
711



716
716

718
720
720



THE ANIMAL KINGDOM.



SUB-KINGDOM I. VERTEBRATA.
CLASS I. MAMMALIA.

BY R. LYDEKKER, B A .. F R S . V P G.S , &c.

IT is a somewhat carious deficiency in the English language that it has no
word of its own that will include all the animals forming the class known to
zoologists as the Mammalia. It is true that the term Beasts properly belongs
to the great majority of the members of the class, but it has also acquired
another meaning, and expressly excludes man. Even more objectionable is
the term Quadrupeds, since not only does this exclude man and the higher
apes, but etymologically includes crocodiles, lizards, and turtles. Accord-
ingly, as neither of these two words are suitable to designate the class as a
whole, naturalists have long been in the habit of using an Anglicised version
of its scientific designation, and at the present day the term " Mammals " has
come so widely into use that no apology for its employment here is called for.
Mammals, then, are tho highest of the Vertebrata, and thus of all animals, and
take their name from the general presence of prominent udders, furnished
with teats, in the female, for the secretion of the milk, by which the young are
invariably fed during the earlier stages of their existence, such udders being
situated in the higher types on the breast, although in many of the lower
forms they are abdominal in position. In the very lowest members of the class
there are, however, no distinct teats, the milk-glands discharging by means
of a number of small apertures in the skin of the lower surface of the body.
It is thus the presence of these milk-glands, and the suckling of the more or
less helpless young, that are the prime essential features of the class.

Before glancing at certain others of their distinctive features, a few words
may be said in regard to the Vertebrata, which form a sub-kingdom, including
the five classes of Mammals (Mammalia), Birds (Aves), Rep-
tiles (Reptilia), Amphibians (Amphibia), and Fishes (Pisces). ^ f vertebrates 8
And here it may be noticed that certain low forms, such as
the lampreys and lancelet (Amphioxus), commonly classed among Fishes, are
now regarded as forming a portion of a lower group known as the Protochor-
data. Vertebrates take their name from the general presence of the struc-
ture termed the vertebral column, or backbone, although in some of the lower
forms this is represented merely by a cartilaginous rod. Whether this struo



THE ANIMAL KINGDOM.



ture be merely such a rod, or whether it be divided into the numerous bony
segments known as vertebrae, it is invariably situated on the dorsal aspect of
the body, or that from which the limbs are turned away. On that side of
the primitive backbone lying nearest to the back, there runs a tube or canal,
formed by arches of bone or cartilage arising from the bodies of the vertebrse,
and containing the great nervous cord commonly spoken of as the spinal
marrow or cord. This cord in the adult state of the higher forms being thus
included within what are called the arches of the vertebrse. On the side of
the primitive backbone opposite to that occupied by the spinal marrow is a
much larger chamber, containing the heart and digestive organs ; so that, in
cross-section, the body of a Vertebrate consists of a smaller nerve-tube lying
above the primitive backbone, and of a much larger tube, containing the
heart and digestive organs below the latter. Throughout the Vertebrates the
limbs never exceed two pairs, and are always turned away from that aspect
of the body containing the nerve-tube ; and the two jaws are upper and
lower, and work against one another in a vertical plane.

In addition to the presence of milk-glands, and the suckling by the young
of the fluid they secrete, the following structural features may be noticed as
distinctive of the Mammalian class. A highly important
* eafcure is the mode of articulation of the lower jaw to the
Mammals skull proper, or cranium ; this being effected by means of a
prominence, or condyle, at the higher portion of the hinder ex-
tremity of the lower jaw, articulating with a special cavity the glenoid cavity
in the cranium. On the other hand, in the lower Vertebrates this articulation is
effected by means of a special separate bone the quadrate articulating above
with the cranium, and below with the lower jaw ; this quadrate, as such,
being absent in the Mammalia. Another peculiarity connected with the
lower jaw is that it consists of a right and left branch connected at the chin
by a bony or cartilaginous union each of which is formed of but a single bone;
whereas in the inferior Vertebrates several distinct bones enter into the com-
position of the two branches. Externally, Mammals are further characterised
by the possession of hair on the skin, although this may be represented
merely by a few bristles in the neighbourhood of the mouth during the earlier
stages of existence. Internally, that portion of the great body-cavity con-
taining the heart and lungs is completely shut off from the chamber in which
are placed the digestive organs by means of a transverse partition, known as



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