244 REPORT—1846€, 
represented by divisions of the compound lower jaw in the crocodile and 
embryo bird (see Tasie, No. III.). The pterygoids (24), the essential di- 
stinction of which from the sphenoid Oken clearly recognises, are his ‘ clavi- 
culz capitis.’ Oken hints at, without accepting, the (serial) homology of 
the hyoid arch with the pelvis; but he regards the stylohyal (ss) as. the 
‘sacrum capitis’ (7b. p. 16). 
The year after the publication of Oken’s famous ‘ Introductory Lecture,’ 
Prof. Duméril, apparently unacquainted with its existence, communicated 
to the French Institute a memoir entitled ‘ Considérations générales sur 
Yanalogie qui existe entre tous les os et les muscles du trone dans les ani- 
maux, the second paragraph of which is headed “ De la téte considérée 
comme une vertébre, de ses muscles et de ses mouvements.” In this para- 
graph, repeating the homological correspondences, demonstrated by Oken, 
between the basioccipital as a vertebral centrum, the condyles as ‘ oblique 
processes,’ and the occipital protuberance as a spinous process, he adds, that 
the mastoid processes are entirely conformable to transverse processes. And 
M. Duméril has, I believe, here the merit of having first enunciated the 
general homology of the mastoids, although he does not aim at showing to 
which vertebral segment of the skull they properly belong. Nor, indeed, 
-with the exception of an observation that ‘ very often the body of the sphe- 
noid, like the ‘apophyse basilaire’ of the occiput, resembles the body of a 
vertebra,” does he push the transcendental comparisons further. Geoffroy 
St. Hilaire tells us*, that even the moderate and very obvious illustrations 
of the general homologies of the cranial bones, which M. Duméril deduced 
from the anatomy of the occiput, excited an unfavourable sensation in the 
bosom of the ‘ Académie; and that the phrase ‘ vertébre pensante,’ which a 
facetious member proposed as an equivalent for the word ‘ skull,’ and which 
circulated, not without some risibility, along the benches of the learned 
during the reading of the memoir, reaching the ears of the ingenious author, 
the dread of ridicule checked his further progress in the path to the higher 
generalizations of his science, and even induced him to modify considerably 
many of the (doubtless happy) original expressions and statements in the 
printed report, so as to adapt it more to the conventional anatomical ideas 
of his colleagues. 
As the truth of Oken’s generalization began to be appreciated, it was remem- 
bered, as is usually the case, that something like it had occurred before to 
others. Autenrieth and Jean-Pierre Frank had alluded, in a general way, to 
the analogy between the skull and the vertebral column : Ulrich, reproducing, 
formally, Oken’s more matured opinions on the cranial vertebre, says, 
“ Kielmeyerum preeceptorem pie venerandum quamvis vertebram tanquam 
caput integrum considerari posse in scholis anatomicis docentem audivi.’ 
And the essential idea was doubtless present to Kielmeyer’s mind, though 
he reversed M. Duméril’s proposition, and, instead of calling the skull a ver- 
tebra, he said each vertebra might be called a skull. But these anticipations 
detract nothing from the merit of the first definite proposition of the theory. 
It would rather be an argument against its truth, if some approximative idea 
had not suggested itself to other observers of nature, who only lost the merit 
of developing it, from not appreciating its full importance. He, however, 
becomes the true discoverer who establishes the truth: and the sign of the 
proof is the general acceptance. Whoever, therefore, resumes the investiga- 
tion of a neglected or repudiated doctrine, elicits its true demonstrations, 
and discovers and explains the nature of the errors that have led to its tacit 
* Annales des Sciences Naturelles, t. iii. 1824, p. 177. 
