REMARKS ON THE FIGURES OF PLATE IV. 
ee 
SIMILAR PARTS ARE ADDED TO SIMILAR VERTEBRAL QUANTITIES. 
F’ to equal things we add equal things, respectively, the wholes will be equal. Uniformity and difformity, 
like equality and inequality, is original plus quantity, having undergone the process of subtraction. 
The persistence of plus quantities is the maintenance of uniformity amongst them. The subtraction of 
elementary parts from one or more of such plus quantities, is the introduction of variety amongst these 
figures. But the comparison of minus and plus quantities invariably teaches us that uniformity and variety is, 
in its essence, nothing more than equality and inequality. Thus. if a + 6,and a+ are in all respects equals, 
counterparts, or homologues, then variety or inequality may difference these twin homologues or Gemini by 
rendering one of the quantities in the condition of a—6 which when it shall now be compared with the 
persistent quantity a + 6 must teach us the fact that 0 is a lost quantity, and thus by the rule of comparison we 
are enabled to create the idea of a quantity actually lost by natural subtraction just as clearly as if we had 
ourselves subtracted it. When we dismember the costa from the dorsal vertebra we then subtract from a 
plus quantity which Nature herself has left persistent, and by this subtraction ’tis we ourselves who create 
variety. When again we restore the costa to its natural place we then equate whole quantities by the 
addition of equal things. 
The figures marked A are cervical vertebre. Those 
marked B are of the dorsal class of vertebrae. Those 
marked C are of the lumbar class, and those marked D are 
of the sacral order. All these several classes of vertebre 
of the human spine contain homologous elements, all hold 
identical quantities, and all are in general construction 
and character homologous to one another. 
The figures marked A” B’C” and D” show equal num- 
bers of elemental nuclei. Those nucleary pieces are simi- 
larly marked in each. The dorsal vertebral figure B” is 
now seen to be equated with the cervical fig. A”, and also 
with the lumbar fig. C”, and with the sacral vertebra D”. 
What is that element which by being added to the dor- 
sal vertebra B” renders it equal to all other vertebre of the 
cervical, lumbar, and sacral regions? It is the part of a 
thoracic rib. 
In fig: A” we have marked the posterior exogenous 
moiety of the transverse process 2. The same figure in 
B’C” and D” indicates the like exogenous piece. 
In fig. A” we have also marked the anterior autogenous 
moiety of the transverse process with the letter d, and this 
letterindicates the homologous element in fig. B’” C” and D”. 
In fig. B” the part marked 0 is the proximal end of a 
rib. In figs. A”C” and D” the homologous elements 
marked 6 are similar to that part named 6 in fig. B”. 
These are one and all autogenous elements, and stand in 
the very same position with relation to the vertebral cen- 
trum marked 6 and the exogenous process marked 2. 
Now figures A’A” A” are evidently the homologues of 
each other; so also are figs. B’B” B’”; so in like manner 
are figs. C’C’C”: and figs. D’D” D” are also homolo- 
gous.. ‘These several species of forms are produced of 
identical elements equal both as to number, position and 
cast. 
If fig. A’ be homologous with fig. A” or fig. A” both 
in general and elementary character; so also is it by the 
same evidences homologous with fig. B, or C, or D, for the 
like elementary pieces are to be found in them all. Those 
pieces are similarly marked in each form, read from above 
downwards. Even the foramina and apertures are identical 
ineach. The vertebral foramen 8 of the transverse compound 
process of fig. A” is analogous to the costo-transverse cleft 
8 of fig. B’. This aperture 8 is obliterated in figs. C” and 
D” in consequence of the complete fusion of the parts 
marked 2 and 0 of the same forms. 
Figures E’E” EH” represent the last caudal bones of the 
human spinal series. Around them is drawn the outline 
of the vertebral quantity from which they have been meta- 
morphosed, and with which quantity they may be equated. 
It is by this rule of equations that we are enabled to esta- 
