xiv CONTENTS. 



CHAPTER XLVIII. 



Divisions of the Gasteropoda Prosobranchiata Opisthobranchiata 

 Heteropoda Pulmonate Gasteropoda Families of the Gastero- 

 poda, 290-297 



CHAPTER XLIX. 

 Pteropoda General characters Divisions Families, . . 297-298 



CHAPTER L. 



Cephalopoda General characters Arms Respiratory organs Re- 

 productive process Shell Divisions, ..... 299-304 



CHAPTER LI. 



Dibranchiate Cephalopods General characters Octopoda Argon- 

 autidae Octopodidas Decapoda Teuthidae Sepiadae Spiru- 

 lidae Belemnitidse Tetrabranchiate Cephalapods Structure 

 of the Pearly Nautilus Shell of the Tetrabranchiata Nautilidse 

 Ammonitidae Families of the Cephalopoda, . . . 304-312 



CHAPTER LIT. 

 Distribution of the Mollusca Proper in time, .... 312-315 



Tabular view of the chief subdivisions of the Invertebrata, . . 315-319 



PART XL-VERTEBRATE ANIMALS. 

 CHAPTER LIII. 



General characters of the Vert ebrata Osseous system Digestive sys- 

 tem Blood Circulation Respiration Nervous system 

 Organs of sense Reproduction Divisions, . . . 323-339 



CHAPTER LIV. 



General characters of Fishes Integumentary system Osseous system 

 Fins Respiration Circulation Digestive system Swim- 

 bladder Nervous system Olfactory organs Reproduction, 340-352 



CHAPTER LV. 

 Pharyngobranchii Marsipobranchii, ...... 353-357 



CHAPTER LVI. 



Teleostei Sub-orders Malacopteri Anacanthini Acanthopteri 



Plectognathi Lophobranchii, . . . . . 357-364 



