Chap. YII. 



OSTEOLOGICAL DIFFERENCES. 



277 



To return to the skull of Polish fowl s. The posterior part, viewed 

 externally, differs little from that of 67. bankiva. In most fowls 

 the postenor-lateral process of the frontal bone and the process of 

 the squamosal bone run together and are ossified near their ex- 

 tremities : this union of the two bones, however, is not constant in 

 any breed ; and in eleven out of fourteen skulls of crested breeds, 

 these processes were quite distinct. These processes, when not 

 united instead of being inclined anteriorly, as in all common breeds, 

 descend at right angles to the lower jaw ; and in this case the longer 



Fig. 35. — Longitudinal sections of Skull, of natural size, viewed laterally. A. Polish Cock. 

 B. Cochin Cock, selected for comparison with the above from being of nearly the same 



axis of the bony cavity of the ear is likewise more perpendicular, 

 than in other breeds. When the squamosal process is free instead 

 of expanding at the tip, it is reduced to an extremely fine and 

 pointed style, of variable length. The pterygoid and quadrate bones 

 present no differences. The palatine bones are a little more curved 

 upwards at their posterior ends. The frontal bones, anteriorly to 

 the protuberance, are, as in Dorkings, very broad, but in a variable 

 degree. The nasal bones either stand far apart, as in Hamburghs, 

 or almost touch each other, and in one instance were ossified 

 together. Each nasal bone properly sends out in front two long 



