CONTENTS. XI 



CHAPTER III. 



PAGE 



THE ARTICULATA OR ARTICULATES 282 



SECTION I. THE ARTICULATA CONSIDERED AS A BRANCH.. 282 



SECTION II. THE CLASS OF IN SECT A OR INSECTK/VNS 28~> 



Sub-Section I. The Insecta Considered as a ('lass 2s.~> 



II. The Order of Hexapodaor Insects proper. 2s? 



III. The Order of Araclinida or Spiders, etc.. . 3' i> 



IV. The Order of Myriapoda or Myriapods.. . 347 

 SECTION III. THE CLASS OF CRUSTACEA OR CRUSTACEANS. 34J 



Sub-Section I. The Crustacea Considered as a Class 341) 



II. The Order of Decapoda or Crabs, Lob- 

 sters, etc 355 



III. The Order of Tetradecapoda or Fourteen- 



footed Crustaceans 362 



IV. The Order of Entomostraca or Entoinos- 



tracans 364 



SECTION IV. THE CLASS OF VEKMES OR ANNULATA OR 



WORMS 370 



Sub-Section I. The Worms Considered as a Class 370 



II. The Order of Dorsibranchiata or Lob- 

 worms, etc 375 



III. The Order of Tubicola or Serpulas, etc.. . 378 



IV. The Order of Terricola or Earth-worms. . 379 

 V. The Order of Gephyrea 379 



VI. The Order of Discophora or Leeches 380 



VII. The Order of Trematoda or Flukes 381 



VIII. The Order of Cestoidea or Tape-worms. . 382 



IX. The Order of Turbellaria 384 



X. The Order of Acanthocephala or Spine- 

 headed Worms 385 



XI. The Order of Nematoidea or Thread-like 



Worms 385 



XII. The Order of Rotifera or Wheel-animal- 

 cules 387 



CHAPTER IV. 



THE MOLLUSCA OR MOLLUSKS 390 



SECTION I. THE MOLLUSCA CONSIDERED AS A BRANCH. . .. 390 



SECTION II. THE CLASS OF CEPHALOPODA OR CEPHALOPODS 394 



Sub-Section I. The Cephalopoda Considered as a Clnss. . 394 

 II. The Order of Dibranchiata or Two-gilled 



Cephalopoda 396 



III. The Order of Tetrabranchiata or Four- 



gilled Cephalopods 399 



SECTION III. THE CLASS OF GASTEROPODA OR GASTERO- 



PODS 401 



SECTION IV. THE CLASS OF ACEPHALA OR LAMELLIIJRAX- 



CHIATA OR BIVALVES. . 419 



