CONTENTS. Xlll 



CHAPTER XXIV. 



General characters of the Cephalopoda Mandibles of the Cephalo- 

 pods Ink-sac, shell, and internal skeleton Divisions General 

 distribution of the Cephalopoda in time, .... 272-277 



CHAPTER XXV. 



General characters of the Tetrabranchiata Anatomy of the Pearly 

 Nautilus Shell of the Tetrabranchiata Distribution of the 

 Tetrabranchiata in time Nautilidae Orthoceratidae Ammoni- 

 tidae Shell of the Ammonitidse Distribution in time of the 

 Ammonitidas Genera of the Ammonitidae, . . . 277-293 



CHAPTER XXVI. 



General characters of the Dibranchiate Cephalopods Distribution of 

 the Dibranchiata Octopoda Argonautidae Octopodidae De- 

 capoda Teuthidae Sepiadae Spirulidae Belemnitidse, . 293-299 



CHAPTER XXVII. 



General characters of the Vertebrata General structure of the Verte- 

 brate skeleton Classes of the Vertebrata General distribution 

 of Vertebrata in time, ....... 299-306 



CHAPTER XXVIII. 



General characters of the Fishes Scales of Fishes Skeleton of 

 Fishes Limbs of Fishes Median fins of Pishes General dis- 

 tribution of Fishes in time, ...... 306-315 



CHAPTER XXIX. 



Teleostean and Ganoid Fishes General characters of the Teleostei 

 Sub-orders of the Teleostei Malacopteri Anacanthini Acan- 

 thopteri Plectognathi Lophobranchii General characters of 

 the Ganoidei General distribution of the Ganoids in time 

 Classification of the Ganoids Amiadse Lepidosteidae Lepi- 

 dopleuridse Crossopterygidae Families and distribution of the 

 Crcssopterygious Ganoids Ostracostei Sturionidae, . . 315-333 



CHAPTER XXX. 



Elasmobranchii and Dipnoi General characters of the Elasmo- 

 branchii General distribution of the Elasmobranchii in time 

 Holocephali Plagiostomi, general characters and divisions of 

 Cestraphori Cestracionts of the Upper Ludlow Rocks Hybo- 

 donts and Acrodonts Selachii Batides General characters of 

 the Dipnoi Characters of the Barramunda Palaeichthyes of Dr 

 Giinther, . ... . 334'345 



CHAPTER XXXI. 



Amphibia General characters of the Amphibia Distribution of 



Amphibians in time Urodela Anoura Labyrinthodontia, 346-353 



