2} REMARKS ON THE FIGURES OF PLATE XXXVI. 
genetic or plus variety; even as the opposite extremity 
of the sternum, which, where it joins the linea alba by the 
xiphoid cartilage, presents all sorts of genetic changes. 
In all the figures it will be noticed that the median 
line passing from a, through 0, through ¢, to d, the sub- 
pubic region, is a line within whose range numberless 
varieties of nucleary deposit is occurring; and this is so 
true that the human anatomist has long since owned to the 
fact, that no one description of sternal form and develop- 
ment is sufficient to include all its varieties of cast. 
The common median line in front traverses the thoracic 
sternum, the abdominal linea alba, and the pubic sym- 
physis. 
is constantly occurring. 
Within this line variety, as to nucleary deposit, 
From a, the episternal ossicles, 
to d, the subpubic osseous nucleus seen in figs. A, B, 
and D, may be noticed a range of line subjected to. mani- 
fold genetic changes; and the only reason which can be 
assigned for this is that it is a region where quantity has 
been subtracted for special modification, and hence is 
liable to all those plus “anomalies” of skeleton deposit 
which may have creation: between the lowest minus quan- 
tity and the highest condition of plus archetype structure. 
From the abdominal region of series original skeleton 
quantity has been subtracted. Of what cast of form is that 
quantity which has been subtracted? It can be no other 
than that of costo-sternal type, and if this assertion cannot 
be upheld by the rule of serial and symmetrical homology 
proper to the human skeleton axis, then other proofs may 
be had, in which that quantity which we have said is lost 
at the abdominal region of the opposite figures, is actually 
persisting at other skeleton venters. For the present, 
however, we will not pass beyond the demonstrable subject 
of the accompanying drawings, nor attempt to stretch 
farther into the law of skeleton formation than simply to 
state in this place that the human abdomen results in 
skeleton series by the metamorphosis of certain skeleton 
archetypes, and that the “anomalies” of form which are 
constantly occurring at the median line in front are all 
explicable and included by this mterpretation. 
In figs. E, F, G, and H, will be also noticed the fact 
that the sternal structure still presents varieties as to 
nucleary development. Likewise that the hyoid appa- 
ratus is produced above the sternum im the cervical region, 
and that it falls within the range of the median line of 
cleavage. This common median line passing downwards 
from the point marked a, in figs. EH, F, G, and H, would 
first cleave the hyoid bone through its body, next the 
thyroid figure, also through its centre, next the cricoid 
form through its mid region, and then would cleave 
the sternal centre from / to 6, and continue its passage 
through the linea alba to-the navel c, and the pubic sym- 
physis d. Thus, all regions of this common median centre 
in front, and all structures, whether plus or minus, which 
appear within its range, are rendered bipartite by the one 
act of sundering, just as completely as if those several 
regions and created structures presented of one appear- 
ance, and that no other condition of variety disconnected 
their enchained relationship than that of plus rendered 
minus. Be this as it may, however, the above reading — 
can only be offered in this stage of the argument as a 
mere suggestion, for we are as far from stating that the 
hyoid apparatus is exactly homologous to a sternal struc- 
ture in the human body, as we are from regarding the 
lineze transversze and linea alba to be the complete homo- 
logue of either of the above. . But it will be at least 
granted that the common median line bisects all the forms 
which take serial order from the symphysis maxill to the 
symphysis pubis, and also that if, at present, reason forces 
us to admit that absolute identity cannot be proved 
between the hyoid apparatus and the sternal structure, 
still we must also acknowledge to the truth, that the hyoid 
apparatus is not in all cases similarly developed, neither 
can the sternal structure be said to be developed in all 
cases alike. 
We must also admit that the several sternal pieces from 
k, to 6, im fig. H are not absolutely identical with each 
other, nor can the sternum of fig. H be called the homo- 
logue of that in fig. G, or F, or E. 
Neither can it be asserted that the linea alba and linez 
transverse of fig. D are homologous to those seen in fig. C, 
or B, or A. In the abdominal median line of those several 
figures from the xiphoid cartilage marked 6, to the pubic 
symphysis marked d, occurs the umbilical knot c, always 
at the same locality ; but from this common centre ¢, to the 
sternal point 0, above, and to the symphysis pubis d, below, 
there happen many genetic difformities, both as to the 
number of the fibrous transverse lines, cartilaginous, and 
osseous deposits. If, therefore, there would seem to be at 
present good reason for denyiug the absolute identity 
between hyoid and sternal pieces, so would there seem to 
exist as good a reason for denying the absolute identity 
between those structures which at present bear the 
common name of hyoid apparatus, or those which are 
called sternal, or those which are named abdominal fibrous 
intersections. 
But as we have before observed that all creations of minus 
apparatus which appear at a region from whence quantity 
has been subtracted from the plus archetypes of the serial 
axis may perform all modes of variation as to quantity 
between the extremes of plus and minus development, so 
must it at once appear impossible to read an absolute 
homology as to the quantities proper to those several 
structures; and. this is the actual state of all structures 
happening at the median line in front. ; 
In figs. E, F, G, and H, we have represented the plus 
and minus varieties of the costo-vertebral units consti- 
Those varieties are pro- 
portionals of the thoracic archetype quantity. From /, 
the first thoracic rib, to g, the last asternal rib, and from 
tuting the serial skeleton axis. 
this latter form to A, the autogenous costal piece of the 
lumbar unit, we easily discover the law of metamorphosis 
or proportioning. Granting, therefore, that g, and h, are 
minus proportionals of the full costo-vertebral thoracic 
quantity to which f; belongs, it must result that when we 
equate g, or h, with f, that is to say, minus with plus, we 
are actually creating, by this very process of reasoning, 
