GENERAL AND SPECIAL TERMS IN OSTEOLOGY. 221 



ton,' the expression of such knowledge has necessitated 

 the use of general terms, such as " vertebra," for the seg- 

 ments of the skeleton, " neurapophyses," for a constant 

 element of such segment, and the like "general names" 

 for other elements. When any of these elements are 

 modified for special functions, then also a special name 

 for it becomes a convenience, as when a "pleurapophy- 

 sis" becomes a jaw or blade-bone, &c., a " diverging ap- 

 pendage" an arm or a leg. Deep thinking anatomists 

 have heretofore caught glimpses of these higher, or more 

 general, relations of the vertebral elements, when much 

 modified or specialized, as e. g. in the head, and have tried 

 to give expression to the inchoate notion, as when Spix 

 called the " maxillary arch" the " arm of the head." These 

 glimpses of a great truth were, however, ill received ; and 

 Cuvier alluded to them, with ill-disguised contempt, as 

 being unintelligible and mystical jargon, in his great work 

 on Fossil Animals (1825). But the error or obscurity 

 lay rather in the mode of stating the relationship of cer- 

 tain bones of the head to those of the trunk, than in the 

 relationship itself: in the endeavor, e. g. to express the 

 relation by special instead of general terms. Even in 

 1845, the learned and liberal-minded editor of Baron Cu- 

 vier's last course of lectures, M. de Saint Agy, comment- 

 ing upon the osteological essays of Spix and Oken, 

 remarks: "For my part, an 'upper-jaw' is an 'upper-jaw,' 

 and an 'arm' is an ' arm.' One must not seek to originate 

 an osteology out of a system of metaphysics."^ But a \ 

 jaw is not the less a jaw because it is a "hasmapophysis,"! 



* "Pour raoi, une maclioire superieure est une machoire superieure, 

 et un bras est un bras. 11 ne faut pas chereber ^ faire sortir I'osteologie 

 d'un sy,st&rae de metaphysiquo." 



19^ 



