REMARKS ON 
THE FIGURES 
OF PLATE V. 
THE LAW OF SERIES EXPRESSES THE LAW OF UNIFORMITY. 
SSEOUS quantities, such as those which constitute the spinal series, are repetitions of each other. 
The 
vertebree of those several regions of the spinal axis, which anatomists name cervical, dorsal, and lumbar, 
contain identical elements, and thus the original or standard character of a skeleton serial axis being that of 
uniformity, the idea which fixes upon uniformity will best appreciate the design occurring by special 
modification. 
Serial figures which are produced of primary identical elements will, when viewed as such, 
express that transitional change by which secondary design has rendered various numbers of those same 
figures as regional fitnesses. 
Thus, while we know that elemental quantity is equal, homologous, and the 
same, for vertebral forms of either the cervical, dorsal, lumbar, or sacral regions of series, we then, compared 
with this original oneness of type, clearly understand how far Nature has, as it were, re-edited her work and 
written the specialty of cast on each compartment of series. 
In fig. A, the front view of the human spinal series, we 
have marked those elemental pieces which hold serial order, 
passing downwards from the dorsal to the lumbar regions. 
The pieces marked a, b,c, d, e, are the heads of the thoracic 
ribs, which stand in serial order with f, g, h, i, k, J, the 
costal atrophied forms of the lumbar spine, and of which 
they are the homologues. 
The pieces marked a, 8, ¢, d, e, of fig. A are autogenous 
elements, and persist articularly separate from the dorsal 
vertebre. In this particular they differ from the autoge- 
nous elements f, g, /, 7, k, 7, of the lumbar spine, to which 
these latter are permanently soldered by ossific deposit. But 
if this condition of development be accounted sufficient to 
establish the character of absolute difformity between both 
orders of the serial pieces, why then, for the same reason, 
we must conclude that a rib is not a rib when it becomes 
consolidated with a dorsal vertebra, and, also, that a lum- 
bar autogenous process is not itself when it shall be dis- 
covered to hold articularly separate, like a rib, from the 
lumbar vertebra. This subject will be hereafter considered. 
It is nevertheless most evident that the costal pieces a, 
b, c, d, e, fig. A, hold serial order with, and are homolo- 
gous to, the autogenous pieces f, g, h, 7, k, 1. If this be 
the simple fact, then it is clear that we call the first order 
of pieces “ribs,” on account of their operating articularly ; 
whereas, we name the latter order of the homologous 
series “transverse processes,” solely on account of their 
being permanently anchylosed to the lumbar vertebree. 
_Now if the pieces a, 4, c, d, e, hold serial order with, 
and identify themselves with the pieces marked f, g, h, 2, k, 
1, then it is clear that we should not confound those latter 
pieces with those marked 1, 2, 3, 4, which are the true 
exogenous transverse processes of the dorsal spine. 
For we see how that in fig. B those exogenous transverse 
processes of the dorsal spine, hold serial order with the 
exogenous “tubercles” of the lumbar spine. The piece 
marked 1 being in serial order with the homologous pieces 
marked 2, 3, 4, 5, 6, 7, 8, 9, 10, whereas, the costal pieces 
of the dorsal vertebrze, marked serially from a@ to e, pass 
into the serial pieces marked from f to &, and also to / 
of the sacral form. 
The fact, therefore, which we seek to establish in this 
place is, that the processes named by the human anatomist 
“ transverse” in the lumbar spine, are not homologous 
with the processes so named in the dorsal spine. In fig. B 
the piece marked / is not homologue of the piece marked 
3, but the piece 3 is the homologue of the piece 8: and 
the piece marked ¢ is homologue of the piece marked h. 
The serial order of the elementary pieces indicate the 
serial homologues. The serial order of dorsal transverse 
processes and lumbar tubercles, together with the fact 
that these processes are in genetic formation exogenous, 
proves them to be homologous. In the same way the serial 
order of the thoracic costal pieces c, d, e, and the autoge- 
nous lumbar projections f, g, 2, 7, k, prove themselves to 
be homologues. 
Any two forms of the same series which shall present 
nucleary pieces equal, as to number and identical as to 
situation, may be taken as uniform quantities. Thus, in 
fig. A, by the addition of the costal piece e, to the last 
dorsal vertebra, we have made it equal to the first lumbar 
vertebra, which, but for the presence of e in the last dorsal 
