46 



X. — On the Intimate Structure of Bone, as composing the Skeleton 

 in the four great Classes of Animals, viz., Mammals, Birds, Rep- 

 tiles, and Fishes, with some Remarks on the great Value of the 

 Knowledge of such Structure in determining the Affinities of 

 Minute Fragments of Organic Remains. By John Quekett, 

 Assistant Conservator of the Museum of the Royal College of 

 Surgeons of England. 



(Read March 18, 1846). 



Professor Owen, when President of this Society, in his first annual 

 address, delivered on the 15th of February, 1841, after alluding to the 

 great importance derived from the use of the microscope, in deter- 

 mining the structure and affinities of minute fragments of fossil wood, 

 goes on to say, "And if the microscope be thus essential to the full 

 and true interpretation of the vegetable remains of a former world, it 

 is not less indispensable to the investigator of the fossilized parts of 

 animals. It has sometimes happened that a few scattered teeth have 

 been the only indications of animal life throughout an extensive 

 stratum ; and when these teeth happened not to be characterized by 

 any well-marked peculiarity of external form, there remained no other 

 test by which their nature could be ascertained, than that of the mi- 

 croscopic examination of their intimate tissue. By the microscope 

 alone could the existence of keuper-reptiles in the lower sandstones 

 of the new red system, in Warwickshire, have been placed beyond a 

 doubt. 



" By the microscope, the supposed monarch of the Saurian tribes — 

 the so-called Basilosaurus — has been deposed, and removed from the 

 head of the reptilian to the bottom of the mammiferous class. The 

 microscope has degraded the Saurocephalus from the class of reptiles 

 to that of fishes; it has settled the doubts entertained by some of the 

 highest authorities in palaeontology as to the true affinities of the gi- 

 gantic Megatherium, and by demonstrating the identity of its dental 

 structure with that of the Sloth, has yielded us an unerring indication 

 of the true nature of its food." 



Now if this be true of the structure of the teeth, which the brilliant 

 results that Mr. Owen has obtained, by carrying out this mode of in- 



