62 



which represents a portion of the scale of the Lepidosteus magnified 

 440 diameters. The other peculiarities in the bone of fish having 

 been mentioned in the preceding paper, and being so entirely different 

 in structure from any other bones of the higher animals, from the fact 

 of their having no bone-cells at all, I need not again allude to them 

 here. The Lepidosiren, then, however much its other true ichthyic 

 characters may prevail, may be said to be, as to the structure of its 

 bones, more like a reptile than a fish ; and thence it may be inferred, 

 that the blood-corpuscles are nearly equal in size to those of the 

 perennibranchiate Reptilia, to which the bone- cells are most nearly 

 allied. 



MEASUREMENT OF BONE-CELLS IN PARTS OF AN ENGLISH INCH. 



Menopome . 



Proteus 



Siren 



Lepioosiben . . 



Pxerodactyle 



Long diameter, 

 Short diameter, 

 Long diameter, 

 Short diameter, 

 Long diameter, 

 Short diameter, 

 Long diameter, 

 Short diameter, 

 Long diameter, 

 Short diameter, 



one of the 

 one of the 

 f one of the 

 (one of the 

 (one of the 

 \ one of the 

 f one of the 

 ( one of the 

 (one of the 

 { one of the 

 (one of the 

 ( one of the 

 one of the 

 one of tbe 

 (one of the 

 {one of the 

 j one of the 

 \ one of the 

 (one of the 

 jone of the 



largest, , J3 . 

 smallest, 7S0 . 

 largest, ^ 

 smallest, 3^. 

 largest, jfo. 

 smallest, g^,. 

 largest, ^j. 

 smallest, B ^,. 

 largest, ,fo. 

 smallest, 3 ^,. 

 largest, 3^. 

 smallest, ^. 

 largest, fa. 

 smallest, ^. 



largest, ,J . 

 smallest, j^. 



largest, -fa- 

 smallest, j^. 

 largest, ^ m . 

 smallest, jjjj. 



