2 INTRODUCTION. 
except that of proportioning, and consequently those plus and minus quantities must be homologous in all 
their characters excepting that one of quantity. Comparative osteology has ever sought to determine the 
unity of organization, upon which all skeleton quantities have been planned ; but as it must be at once 
confessed that minus cannot be uniform with plus, that the part and the whole quantities cannot be equals, so 
therefore it is to the whole quantity, as containing the part, that anatomy must turn if it be destined ever to 
read the original mance form, and the law creative of proportional variety. 
If it be impossible to comprehend aright the passages of a general law without knowing of the whole 
structural quantity upon which that law operates, rendering it proportionably various, so must comparative 
osteology ever fail to demonstrate the law of unity in variety, until it has first stunesetienl the archetype 
figure, of which a vertebra is the proportional. The whole quantity must be unity, and, compared with this, 
all other forms which manifest no other character of dissimilarity than that of quantity, must be estimated as 
the proportionals of such a whole ; and this is the idea which we here entertain of the form vertebra, 
compared to the archetype whole quantity. The vertebra is not an entirety, therefore it must be part of an 
entirety ; and therefore as unity is the character of an entirety, so unity cannot characterise the vertebra. 
A perusal of all the records of anatomy penned between the age of Aristotle and that of Geoffroy, will leave 
this one fact salient within the memory, viz., that it is as impossible to define the form of skeleton unity upon 
the vertebra, as it is to demonstrate the whole quantity in any proportional of itself; and also that it is as 
impossible to define (between any two known vertebral quantities) any other condition of variety except that 
of plus and minus proportioning, as it is between an integer and its fractionals. 
Between the unity and variety of skeleton form, as between the plus and minus of any quantity, there is 
no distinct boundary line possible to be drawn. But if it can be ascertained that unity is rendered various by 
the self-same process of metamorphosis or subtraction, which strikes minus from plus quantity, then it is the 
whole quantity which must be regarded as unity, and it is the simple rule of subtraction from such a quantity 
which must be esteemed as that law which is creative of proportional variety. Under these ideas the origin 
of the name “vertebrated” may be sought for, and we shall find that it was a name affixed to a certain 
osseous quantity developed in the special skeleton serial axis when the science of comparison was unknown, 
and the law of unity in variety* which governs the chain of animal being as yet unrecognised. In the name 
vertebra (derived from vertere) the prerice can discover no meaning which may be said to keep pace “er 
comparative reasoning progressive to the contemplation of whole quantities, or uniformity transmuted by 
alaw. And the abortive special study of Athotis, Hippocrates, Vesalius, or Albinus, is dissipated before the 
science of Daubenton, Goethe, Geoffroy, and Cuvier, in search of general principles. 
A history of the progress and cultivation of anatomical science, from the first observation of a few 
isolated facts of form to that extended sunhontie of the various particularities. of form and structure presented 
in the animal kingdom, and from out of which the science of Comparative Anatomy has sprung to such 
reading as it exhibits in the present day, may be viewed as a type of the progress of an individual mind from 
the early stage of its infantile observations of a limited number of facts, and its premature interpretation of 
the same, to that stage of its adult reasonings when, having heaped together an ample store of materials, it 
* Leibnitz makes use of this term as. expressive of his “loi de continuité.”” He defines. the Universe as ‘‘Vunité dans la 
variété ;”’ he writes, ‘Tout va par degrés dans la nature, et rien par saut.”—See Wwwres Philosophiques de M. de Leibnitz, 
Liy. iv., p. 440. 
