“gaa7 
ON THE VERTEBRATE SKELETON. 317 
precisely those of which the determination has been easiest, and respecting 
‘the names and nature of which there has been the least discrepancy of opi- 
‘nion. It is with pain and a reluctance, which only the cause of truth has 
‘overcome, that I am compelled to notice the inconsistencies into which the 
great Cuvier fell, when his judgement became warped by prejudices against 
a theory, extravagantly and, perhaps, irritatingly, contended for by a con- 
temporary and rival anatomist. After having established by the clearest 
evidence and soundest reasoning in his great and immortal works that the 
‘bones (7) in the fish (figs. 2 and 5) and reptiles (figs. 9, 10, 13, 19, 22) were 
homologous with those in birds (7, figs. 8 and 23), mammals (7, figs. 12 and 
24), and even in man (7, figs. 11 and 25); and, after contending that they 
ought to bear the same name—under which, indeed, we find him describing 
them in the ‘ Lecons d’Anatomie Comparée’ from man down to the fish— 
Cuvier comes at last to declare that, in those animals in which they are 
‘separated from the alisphenoids and mesencephalon, they are “ particular 
pieces which have a particular destination !” 
~The relation of the mastoids (s,s), as parapophyses, to the parietal or 
sphenoidal vertebra not having been detected in Cuvier’s time, he supposes 
that the pterygoids, in the system which makes a vertebra of the sphenoid, 
‘ean be compared to nothing else than the transverse processes of such. As, 
according to my views, they are recognizable in General Homology as quite 
_ distinct elements of another cranial vertebra, the arguments which Cuvier 
advances in disproof of what he thought they must be called, do not concern 
the subject of the present Report. The inferior exogenous processes, in- 
deed, of the basisphenoid in mammals are not unlike those developed from 
the under surface of the centrum of the atlas in Sudis gigas, or from some 
‘of the cervical centrums in birds. The argument founded by Cuvier on the 
autogenous development of the true pterygoid (figs. 24 and 25, 21) would 
weigh little against its parapophysial nature, if other characters concurred 
‘to prove it a ‘ parapophysis;’ but its connections and position show it to be 
-a ‘diverging appendage.’ 
‘With respect to the anterior sphenoid, Cuvier affirms that its composition 
is totally different from that of the posterior sphenoid and occipital, and from 
‘that of any vertebra. By the term ‘ sphénoide antérieure’ is meant the 
“eoalesced presphenoid and orbitosphenoids (figs. 24 and 25, 9 and 10); and the 
two bones referred to in the comparison signify, the one, the basi- and ali- 
sphenoids (i. 5 and c), and the other the basi- and ex-occipitals (#b. 1 and 2). 
‘With respect to 9 and 10, Cuvier remarks that it is never, in mammals, formed 
“of three pieces, but only of two; and that these are properly the bony rings 
‘for the optic nerves, which in course of time approximate and coalesce with 
each other: but so long as the median suture divides them, no distinct or 
“third bony nucleus is developed in the intervening cartilage*. 
» Since, however, we see that the homologues (recognised as such by Cuvier) 
of the orbitosphenoids are something more than rings surrounding the optic 
nerves in the bird (figs. 8 and 23, 10) and crocodile (figs. 9 and 22, s)—that 
they are merely notched by the optic nerves, and are chiefly developed in 
* “Ton a voulu aussi considérer le sphénoide antérieur comme une vertébre dont les 
_frontaux compléteraient la partie annulaire, et ou la position du trou sphéno-orbitaire entre 
les deux sphénoides repondrait assez aux trous inter-vertébraux ordinaires. Mais la compo- 
“sition du sphénoide antérieur lui-méme est toute différente de celle des deux os, dont nous 
avons parlé avant lui, et de celle d’aucune vertébre. Il n’est jamais, dans les mammiferes, 
formé de trois piéces, mais seulement de deux; ce sont proprement des anneaux osseux pour 
les nerfs optiques, qui par suite du temps se rapprochent et se soudent entre eux; la suture 
est toujours au milieu, et tant que V’ossification n’est pas complete, il n’y a entre les deux 
 anneaux que du cartilage, dans Jequel il ne se forme pas de troisicme noyau.”—/. ¢. p. 714. 
