218 REPORT — 1846. 



other hand, in equally general terms, " those who have been unable to elevate 

 themselves to these kind of questions, partly on account of the nature of their 

 minds, partly from the want of proper and sufficient subjects of contempla- 

 tion *." 



Neither the first step, the most difficult of all, nor any of the succeeding 

 steps in the acquisition of such views of the ' Signification of the Skeleton ' 

 as M. de Blainville adopts are noticed : no objection to the vertebral system 

 of the skull is answered: no error that may have opposed itself to a reception 

 of the doctrine is explained or refuted : of the particular labours and dis- 

 coveries of individual nomologists the author of the ' Osteographie' is silent. 

 He defines a vertebra, in the language of anthropotomy, as a single bone : — 

 " Une vertebre, considered d'une maniere generale, et par consequent dans 

 son etat complet, est un os court, median, symmetrique, formant un corps, 

 partie prineipale de la vertebre, aux deux faces opposees de laquelle, externe 

 on dorsale, interne ou ventrale, s'applique un arc plus ou moins developpe, 

 d'ou resultent deux canaux, l'un au dos, l'autre au ventre." (ib. fasc. i. p. 6.) 

 We discern the influence of the ideas of his ingenious contemporary, Geoflroy 

 St. Hilaire, in the admission of the ventral or inferior, as well as the dorsal or 

 superior arch ; and, like Geoflroy, he recognises the physiological relation 

 of the upper arch to the protection of the nervous system, and that of the 

 lower arch to the protection of the vascular system : but, overlooking or re- 

 jecting the idea of the relation of the ribs as the inferior protecting arches of 

 the expanded central organ of the vascular system, he considers the ventral 

 (haemal) arches as arriving at their maximum of development in the tail. The 

 dorsal and thoracic vertebrae are, accordingly, characterized as those which are 

 provided with costiform appendages diversely articulated to them ; over- 

 looking, I mav remark, the costal appendages of the cervical vertebras in the 

 saurians and those which become anchylosed to the cervical vertebrae in 

 birds, as do, frequently, their serial homologues to the dorsal vertebrae in the 

 same class. M. de Blainville seems, also, wholly ignorant of the fact that the 

 bent-forward ends of the long transverse processes of the lumbar vertebrae of 

 the hares, cavies, and many other rodents, are primarily developed as distinct 

 costal rudiments : the same rudiments of lumbar ribs are found in the foetus 

 of the hog, and in the first lumbar vertebra of many mammals f. " Les Iom- 

 baires," says M. de Blainville, " n'ont plus de cotes, meme incompletes." 



The ribs not being regarded as essentially parts of the inferior or haemal 

 arches of vertebrae, the sternal bones which complete these greatly expanded 

 arches are accordingly regarded as a distinct series of bones, and called 

 * sternebers.' M. de Blainville, as we have seen, had before (1817) compared 

 them to vertebral bodies. In the ' Osteographie,' however, he rightly regards 

 the body of thehyoid as their serial homologue, but does not extend his com- 

 parison to the bones that in like manner complete the mandibular and max- 

 illary arches. These, with the cornua of the hyoid, and the sternal and verte- 

 bral ribs, he classes with the bones of the extremities, under the name of 

 appendages (appendices), adopting, in his larger work, as in his original essay, 

 essentially the idea of Oken, that the locomotive members are liberated ribs. 



After much additional research and comparison since the first publication 

 of my ideas of the constitution of the typical vertebra or primary segment 

 of the endo-skeleton }, I have found no reason for modifying them, but have 

 derived additional evidence of their accuracy ; and I therefore reproduce the 

 diagrammatic figure with which they were originally illustrated (fig. 14). 



* Osteographie, Prospectus, April, 1839, p. 5. 



t Thirle, in Muller's Archiv fur Physiologic, 1839, p. 106. 



% Geological Transactions, 4to, 1838, p. 518. 



