220 REPORT— 1846. 
part which appertains to the sense-capsule, i.e. which is directly concerned 
in the support of the membrane and cells of the olfactory organ. 
But leaving for the present the question of names, and returning to things, 
let us pursue our search and comparisons of the bones which continue in the 
higher classes to repeat the essential characters of those called ‘ prefrontals’ 
in fishes. Were it necessary to add to the reasons above assigned for regarding 
no. 14, fig. 13, as the homologues of 14 in the fish, notwithstanding they are 
connate in the batrachian, I would cite the structure and relations of those 
bones in the sword-fish. The whole of the anterior part of the, extensive 
interorbital space is occupied by the prefrontals, which join each other at the 
median line by an extensive vertical cellular surface: they form the anterior 
border of the orbit, and the posterior wall of the nasal fossa; they close the 
cranial cavity anteriorly, and transmit the olfactory nerve to the capsule by 
a central foramen. They are almost entirely covered by the frontals above, 
which they support by a broad flat surface; a very small portion only ap- 
pearing on the upper surface of the skull at the anterior angle of the orbital 
ridge. Were the frontals separated, the prefrontals would then appear, as in 
the frog, at the median line: were the suture between the two prefrontals 
to be obliterated in Xiphias, an ‘os en ceinture’ would be produced like that 
of the frog. The nasal bone of the sword-fish, which Cuvier calls ‘ ethmoide,’ 
presents a cellular structure of its base, designed to break the force of the 
concussion arising from the blow which is delivered by the ‘sword.’ But the 
prefrontals manifest more extensively this peculiar cellular structure, which 
Cuvier well says, “l’on prendrait presque pour les cellules de lethmoide d’un 
quadrupéde*.” 
Cuvier, not perceiving or not appreciating the grounds of the homology of 
the ‘os en ceinture’ with the prefrontals, describes the divided nasal (1s, fig. 
13), in the batrachia as the ‘ frontaux antérieures’ ; and reciprocally, having 
called the bones in fishes, homologous with the bone 14, (which he thought 
might represent the ethmoid in the frog) ‘frontaux antérieures,’ he gives the 
name ‘ ethmoide ’ to the bone 15, fig. 5, whether single or divided, in ‘fishes. 
It is not necessary to add anything to the arguments by which M. Agassiz 
has sustained the conclusion of Spix, that Cuvier’s ‘ethmoid’ in fishes is the 
‘nasal.’ And it needs, I think, only to compare the connections of the 
bones 15, fig. 13, with either the single or the divided nasals in fishes, and to 
glance at the obvious homology of the bones / in Cuvier’s pl. xxiv. fig. 1—6, 
with the bones gg in figs. 4 & 6 of pl. xxvi. (‘ Ossemens Fossiles,’ t. v. pt. 2), 
to ensure the acceptance of the conclusion, that his ‘ frontaux antérieures’ 
in the frog and the other anourans are the true nasal bones. 
In the python Cuvier transfers the name ‘frontaux antérieures’ to the 
lacrymal bones. The bones in this serpent, which are in neurapophysial 
relation with the olfactory nerves, and which present other essential charac- 
ters of the prefrontals (14) in fishes, are also two in number, in the form of 
thin osseous plates, intervening on each side, anterior to the frontal, between 
the vomerine and nasal bones, bent outwards, in the form of a semicylinder 
about the olfactory nerves, which they support and guide to the cartilaginous 
capsule of the organ of smell, and having the palatine bones articulated to 
their under and outer sides. The bones, which thus present every essential 
character of the prefrontals, are those (ss in pl. ix. figs. 1, 2, 3, ‘ Régne 
Animal,’ t. iii. 1830) which Cuvier there calls ‘cornets inférieures.’ But 
the true ‘cornets’ (turbinals) are cartilaginous in serpents as in every other 
reptile, and give attachment to the palatines in no animal. The bones 06 in 
* Hist. des Poissons, t. viii. p. 194. 
