CHAPTER VII 



Resumption of cell question Ossification of cartilage 

 Professor Schwann and Dr. Schleiden Dr. Sharpey 

 and bone development Agassiz' classification of fishes 

 Geological distribution of four classes Bearing of 

 Ganoid scales on Owen's " Odontology" Memoir for 

 Royal Society in 1849 Second memoir for the Royal 

 Society 1850 Professor Kolliker Position of oral teeth 

 in relation to skeleton Oral teeth really dermal 

 structure Huxley's acceptance of this Mr. Charles 

 Tomes Structure of fish bones Links in scale of 

 organisation missing from living forms but found in 

 fossils Links in bones of living fishes and placoid saw 

 fish. 



WHILST these various works were in progress, 

 another interesting subject was occupying my mind. 

 During my medical studies at the London Univer- 

 sity, the Professor of Physiology, Dr. Sharpey, had, 

 as I have already observed, called my attention to 

 some moot questions connected with the structure 

 and development of the bones of the human skeleton. 

 I had never wholly lost sight of this subject, and about 

 the time of which I am now writing I began to give 

 it more serious and systematic attention. But before 



