300 REPORT—1846. 
e.g. in Simia. In the rhinoceros it supports a dermal spine or horn. The 
pleurapophysis (20) or proximal element of the hzmal arch of the nasal ver- 
tebra has its real character and import almost concealed by the excessive 
development of the second element of the arch (21), which resumes in mam- 
mals all those extensive collateral connections which it presented in the cro- 
codile ; and to which are sometimes added attachments to the expanded spine 
of the frontal vertebra, as well as to that of its own segment. The pleurapo- 
physis however, besides its normal attachment to its centrum, 13, sends up a 
process to the orbit, in order to effect a junction with its neurapophysis which 
sometimes appears there, as the ‘ os planum’ of anthropotomy. The hemal 
spine (22) is developed in two moieties, which never coalesce together, al- 
though, in the higher apes, and at a very early period in man, each half 
coalesces with the hzmapophysis, and repeats the simple character of the 
corresponding elements (rami) of the succeeding (mandibular) arch. 
The appendicular element (24) which diverges from the pleurapophysis 
(20), contributes to fix and strengthen the palato-maxillary arch by attaching 
it to the descending process of the parietal centrum (s) ; with which, in most 
mammals, it ultimately coalesces. The other elements of the diverging mem- 
ber of the arch correspond in number and in the point of their divergence 
with those in birds, chelonians and crocodiles. They are two in number, suc- 
ceeding each other, and both become the seat of that expansive development 
which is followed by the multiplication of their points of connection ; thus 
the proximal piece (‘ malar’ 26) articulates in the hog not only with the 
heemapophysis (21) from which it diverges, but likewise with the mucc-dermal 
bone, 73. The distal piece of the appendage (squamosal, 27) expands as it 
diverges, and fixes the naso-hemal arch not only to the frontal pleurapo- 
physis (2s), but also to the frontal, parietal and occipital neurapophyses and 
spines: it also affords, in the hog, as in other mammals, an articular surface 
to the frontal hemapophysis (29). 
The development of an osseous, centre in the cartilage of the snout of 
the hog, and the homologous’£ prenasal’-ossicle in certain fishes, the carp, 
e.g might be regarded as rudiments ‘of terminal abortive segments more 
anterior than the nasal vertebra. The multiplied points of ossification in the 
vomer have been, also, deemed indications of that bone being, like the vome- 
rine coccygeal bone in birds, a coalescence of several vertebral bodies. Of 
course, @ priori, the segments in the cranial region of the endoskeleton 
might as reasonably be expected to vary in number in different species, as 
the segments in the thoracic or sacral regions. I have not, however, been 
able to determine clear and satisfactory representatives of more than four 
vertebrz in the skull of any animal ; and the special ossifications in the nasal 
cartilages appear to me to belong to the same category of osseous parts, as 
the palpebral bones in certain crocodiles and the otosteals. 
Man.— Arriving, finally, in the ascensive survey and comparison of the 
archetypal relations of the bones of the vertebrate skull,at Man, the highest and 
most modified of all organic forms, in which the dominion of the controlling 
and specially adapting force over the lower tendency to type and vegetative 
repetition is manifested in the strongest characters, we, nevertheless, find the 
vertebrate pattern so obviously retained, and the mammalian modification of it, 
as illustrated in the preceding paragraph and diagram, so closely adhered to, 
as to call for a brief notice only of those developments of the common 
elements which impress upon the human skull its characteristic form and 
proportions. 
The neural arch of the occipital vertebra differs from that of the hog by 
a much greater development of the newral spine (fig. 25, 3) and a much less 
