338 REPORT—1846. 
their differential and subordinate characters, and to voluntarily abdicate the 
power of appreciating aud expressing them. The terms ‘secondary’ or 
‘tertiary vertebra’ cannot, therefore, be correctly applied to the parts or 
appendages of that natural segment of the endoskeleton to the whole of 
which segment the term ‘ vertebra’ ought to be restricted. 
So likewise the term ‘ rib’ may be given to each moiety of the hzemal arch 
of a vertebra; although I would confine it to the pleurapophyses when they 
present that long and slender form characteristic of the thoracic abdominal 
region, viz. that part of such modified hzemal or costal arch to which the term 
‘vertebral rib’ is applied in comparative anatomy and the term ‘ pars ossea 
coste’ in anthropotomy : but, admitting the wider application of the term 
‘rib’ to the whole hemal arch under every modification, yet the bony di- 
verging and backward projecting appendage of such rib or arch is something 
different from the part supporting it. 
Arms and legs, therefore, are developments of costal appendages, but are 
not ribs themselves liberated: although liberated ribs may perform analo- 
gous functions, as in the serpents and the Draco volans. 
If then the arms or pectoral members be modified developments of the 
diverging appendage of the scapulo-coracoid arch, and if this be the hzmal 
arch of the occipital vertebra, it follows that the pectoral members are 
parts of the head, and that the scapula, coracoid, humerus, radius and ulna, 
carpals, metacarpals and phalanges, are essentially bones of the skull. 
The transcendentalism, therefore, which requires for its illustration that 
the maxillary arches be the arms and hands of the head, meets its most direct 
refutation in the fact of the diverging appendages, properly called arms and 
hands, belonging actually to one of the modified segments of which the head 
itself consists. 
The head is, therefore, in no sense a summary or repetition of all the rest 
of the body: the skull is a province of the whole skeleton, consisting of a 
series of parts or segments essentially similar to those of which the rest of 
the skeleton is constituted. 
Most of the phrases by which Spix attempted to systematize and carry out 
the repetition-hypotheses of Schelling and Oken, as applied to the osteology 
of the vertebrate skull, may be similarly explained, and when well-winnowed 
some grains of truth may be recovered. 
In denominating the palatine bone the ‘hyoid bone of the f. face,’ Spix en- 
deavours to express a relation of general homology by a term which should 
be confined to the enunciation of a special homology: but he adds “ cornui 
ossis hyoidei anteriori analogum,” which shows an almost correct appreci- 
ation of the serial homology of the palatine bone. It answers, however, in 
the maxillary arch to the stylo-hyal or proximal element of the hyoidean 
arch, not to the cerato-hyal or hemapophysial element ; and it needs only to 
recognise the palatine as the ‘ pleurapophysis’ of its vertebral segment, to 
. eS 
appreciate all its true serial homologies. It might as well have been called the | | 
‘tympanic pedicle of the face,’ the ‘styloid process,’ the ‘scapula,’ the ‘vertebral 
rib,’ or the ‘ilium—of the face’, according to Oken’s and Spix’s faulty method 
of expressing serial homological relations, since it holds in its vertebral segment 
the same place which each of the above-named bones respectively does in its 
segment. 
So also, with regard to the term ‘ os faciei iliacum’ applied by Spix to the 
mastoid (s), the error lies not only in the application of a special term to ex- 
press a general homological relation, but in the supposed serial homology so 
expressed. Had Spix detected, in a cranial vertebra, the precise element 
answering to that called ‘iliac bone’ in a post-abdominal vertebra, yet it 
