326 REPORT—1846. 
of the trunk of the human subject according to the archetype with which the 
segments in the head have been illustrated. 
The first seven segments of the trunk consist each of centrum (fig. 25, e), 
neurapophyses(z), neuralspine (s), and rudimental pleurapophyses(p/), which - 
coalesce, in each segment, into one bone, called ‘ cervical vertebra’ in anthro- 
potomy. If the hemapophyses (s2') have the same relation to their centrum 
which those of the seventh dorsal vertebra, in the Ciconia Argala, more ob- 
viously bear to theirs,—that is, being attached below and disunited at theirupper 
ends from their pleurapophyses, which are short, stunted and anchylosed to the 
centrum,—and if, as the apparent homologues of 52’ in fishes would indicate, 
the atlas be actually the centrum to which such detached and shifted hema- 
pophyses belong, then the first wilkbe the sole segment of the cervical region of 
the trunk in which those elements are ossified. 
In the seven vertebra which succeed the cervicals the pleurapophyses (p/) 
are progressively elongated; they are shifted from their proper centrum to the 
interspace between it and the next segment above, or in advance, and retain 
their moveable joints. The hemapophyses (/) are cartilaginous and articulate 
with the ends of the pleurapophyses and with the hemal spines (As), which are 
flattened, slightly expanded, and ultimately blended into one bone called ‘ ster- 
num. The hzmal spine of the first typical segment remains longest distinct : 
it receives, also, the extremities of the displaced heemapophyses (s2’) and has 
been called ‘ manubrium sterni.’. The hemal spine of the seventh segment 
commonly continues longer distinct, and is later in becoming ossified, whence 
it is called ‘ ensiform cartilage’: it probably includes the rudiments of some 
succeeding hzmal spines. In the four succeeding segments the pleurapophyses 
become progressively shorter, and the hemapophyses, still cartilaginous, are 
severally attached by their lower attenuated ends to the pair in advance ; 
leaving the hemal arch incomplete below. In the next vertebra (19th from 
the skull) the still shorter pleurapophyses resume the exclusive articulation 
with their proper centrum ; and the correspondingly short and pointed hem- 
apophyses terminate freely. 
Those pleurapophyses and hemapophyses which directly articulate with 
hemal spines (sternum) are called collectively ‘true ribs’ (cost vere), the 
proximal element being ‘the bony part of the rib’ (pars ossea coste), the distal 
one the ‘cartilage of the rib.’ The rest of the hemal arches which are in- 
complete through the absence of the hemal spine, are called ‘false ribs’ 
(costz spuriz); and the last, which terminates freely in the origin of the 
diaphragm, is a ‘ floating rib.’ The centrum, neurapophyses and neural spine 
of each segment with freely articulated pleurapophyses coalesce into one bone, 
called ‘ dorsal vertebra’ in anthropotomy : these vertebre are twelve in 
number. Each of the five succeeding segments is represented by the same 
elements (centrum and neural arch) coalesced that constitute the so-called 
dorsal vertebre : they are called ‘lumbar vertebre ' (fig. 25,L.): they have no 
ossified pleurapophyses ; and the hemapophyses of these segments are repre- 
sented only by the aponeurotic ‘inscriptiones tendinez musculi recti’ (”). 
Certain elements of the five succeeding segments (7b. S.) coalescing together 
in the progress of growth form the bone called ‘sacrum’: and are described in- 
dividually as sacral vertebra. The first four of these each combine the same 
elements, coalesced, as in the neck; viz. centrum, neurapophyses, neural spine, 
and short but thick pleurapophyses*: in the fifth sacral vertebra there are no 
* J. Miiller notices the rudimental ribs in the first and second sacral vertebre of the 
human foetus in his Anatomie der Myxinoiden, heft i. 1834, p. 240. Mr. Carlile has 
described (Report of British Association, 1837, p. 112), and Dr. Knox has figured (Lancet, 
1839, p. 191) these ribs and their homotypes in the third and fourth sacral vertebre. 
