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REMARKS ON THE FIGURES OF PLATE III. 
THE DORSAL TRANSVERSE PROCESSES ARE DISTINGUISHED FROM THE LUMBAR TRANSVERSE PROCESSES. 
pes spinal axis is an example of serial order, and between the vertebral quantities of this axis, as 
between all other organic products which Nature develops in series, she never interrupts that order by 
any other condition of variety than that which minus bears to plus quantity. A geometrical or an arithmetic 
Series is similar to a vertebral series in this particular, viz—that in one, as in the other, calculations of the 
differential and the integral quantities may be made. The negative or non-existent quantity which causes 
differences between plus and minus through decreasing series, is inseparable from the consideration of the 
positive or existing quantities which increase from minus to plus, through increasing series. The vertebral 
axis 1s a finite series by the subtraction of quantity, and hence may be symbolically expressed by 1,4, 4, 4, 
is» sx, &c. Now, just in the same way as we find that subtraction from vertebral quantities does, at length, 
terminate series at the last caudal centrum, so will we discover, that all the elementary pieces of vertebrze 
hold serial relation with each other, and, at last, terminate in a vanishing point, by the same process of 
subtraction. The dorsal transverse processes continued from the posterior or exogenous pieces of the 
cervical transverse processes, and passing into the lumbar tubercles, are lost upon the sacral structures at 
- their posterior aspect. 
Fieure A represents a posterior view of the serial spine 
of the human figure. The serial regions named cervical, 
dorsal, lumbar, sacral, and caudal, present some slight 
modifications of form; but the elementary nuclei which 
fashion those vertebre of the several regions, are unmis- 
takeable as to their own proper character. Thus the last 
caudal bone is a vertebral centrum, and as such, holds 
series with no other elementary part of any other vertebra 
of series than that called the centrum. The posterior or 
exogenous apophysis of the cervical tran8verse process, is 
still continuous in series with the same named part of the 
dorsal, the lumbar, and sacral spine. 
The exogenous element, named transverse process of the 
dorsal vertebra, is marked 1 in fig. A, and holds seriatim 
order with the like elements which pass down upon the 
lumbar region, and which are marked 2, 3,4, 5,6,7; but 
the autogenous elements of the lumbar spine which are 
marked a, 0, c, d,e,f, are not to be confounded with the 
transverse exogenous processes of the dorsal spine. 
The transverse processes of the dorsal spine are exoge- 
nous, and pass into the lumbar spinal region under the 
name of “Tubercles.” Those tubercles are also exogenous, 
and if we would fully identify them with their fellows of 
the dorsal spine, we have only to compare the fixed and 
unvarying position of both. The lumbar exogenous tuber- 
cles and the dorsal exogenous processes project severally 
from that primary piece which fashions the half of the 
neural arch. 
It is evident that the piece c of fig. A is not®the piece 
5 of fig. A. It is also evident that the exogenous process 1, 
holding serial order with the exogenous processes 2, 3, 4, 5, 
of the lumbar spine, leaves it to be understood that all 
those processes are homologous; hence it must be evident 
that those processes 1, 2, 3,4, 5, 6,7, are not homologous 
with the autogenous processes a, J, c, d, e, f; therefore, 
those processes which are usually named “transverse” in the 
dorsal spine, are not homologous with the processes usually 
so named in the lumbar spine. The dorsal spine of fig. A 
shows its exogenous transverse processes to be homologous 
with the exogenous tubercles 2, 3, 4, 5, 6, 7, of the lumbar 
spine ; but the dorsal spine as seen in fig. A. holds no ele- 
ments which may be called the counterparts or homologues 
of the lumbar elements a, 3, c, d, e, f- 
Those processes a, 0, ¢, d, e, f, which are usually named 
“transverse” of the lumbar spine, are not homologous with 
the processes commonly named “transverse” of the dorsal 
spine. The former processes are autogenous, the latter 
are exogenous. . 
Fig. B is a front view of the human spinal series. The 
autogenous transverse processes @, 0, c, d, e, f, of the lumbar 
