2) REMARKS ON THE FIGURES OF PLATE XXV. 
Fig. B shows the same first lumbar unit, 1 Ja, to present 
on both its sides the small costal forms marked a, and we 
see that those forms do not exceed the dimensions of the 
autogenous pieces a, a, of the succeeding unit marked 2, at 
the same time that they are articularly operative upon 
the vertebral centrum, like the last ribs of the thoracic 
series. All those pieces marked a, in fig. B, are serial 
homologues proportionally varied. 
Fig. C shows that the lumbar spine is reduced to the 
number of four vertebre, and the thoracic series increased 
to the number of 18, by the simple fact of the autogenous 
pieces of the unit marked 1/a, being produced to costal 
form. 
Fig. D represents how the lumbar spine increases beyond 
the normal number of five vertebre, at the same time that 
the thoracic series diminishes to the number of 11, costo- 
vertebral forms, by reason of the fact that the costz ordi- 
narily developed upon the sides of the unit 12 d, are now 
reduced to the minus quantities marked aa. 
It would appear, therefore, that serial proportioning is 
~ that law which reduces plus quantity to minus, and once 
admitting this undeniable fact, that the first lumbar ver- 
tebra, whatever be its numerical position in series, is a 
proportional of the last thoracic costo-vertebral quantity, 
there can be no reason why we should not also conclude 
that the serial vertebra, wherever produced, is as the pro- 
portional of the fullest thoracic figure. 
A comparison made between figs. A, B, C, and D demon- 
strates the fact that the same numerical unit in series is 
not always existing of the same proportions, and that con- 
sequent upon this variation from plus to minus happens 
the circumstance that the same unit is at one time of 
thoracic series, and at another time of lumbar series. 
When the unit 1 Za, of fig. C, is plus, then it ranks with 
thoracic quantities ; and when, again, this unit 1/ a, of fig. 
D, is minus, then it takes order with lumbar quantities. 
And fixing the attention upon this particular, we isolate it, 
and withdraw ourselves from the overwhelming general 
theme of unity under metamorphosis, in order to begin 
with the apx7 of the process, and thereupon to determine 
the common source whence issue the confederate streams 
of uniformity and speciality. 
Relationary facts yield the combined evidence of a law. 
Comparison is the instrument whereby analogous opera- 
tions are made to express their one and general character. 
A phenomenon indicates its own natural connexion with 
all similar phenomena. These, collectively considered, 
constitute a law, and this law is expressed by a general or 
abstract term. From several particular propositions, in- 
ductive reasoning infers one general rule or law, and thus 
it is that a Franklin establishes identity between the phe- 
nomenon of a galvanic battery and the lightning of the 
cloud ; thus a Newton identifies the phenomenon of attrac- 
tion manifested between bodies and the earth, between the 
moon and the earth, between the planets and the sun, to 
be one general agency ; and thus, also, by an extension of 
the like observation, the expectant Le Verrier proclaims 
the advent of a planetary stranger already created within 
the firmament of analogical reasoning, before its own per- 
son became demonstrable in Nature. Comparison which 
is conducted behind the breastwork of anatomical facts, is 
The 
unity of type has become the theme of anatomical science, 
but as it still remains an unsettled question whether the 
anatomical law gravitates more to the side of unity or to 
that of diversity (a fact which hangs suspended somewhere 
between the doctrines of Geoffroy and Cuvier), so may 
any one, standing before the altar of Nature, assume to 
himself the right of searching through her volume, and of 
thinking for himself whilst engaged in the measurement of 
both these subjects. 
Now, the weight of a reputation, however ponderous it 
may be when compared with that name which has no 
moment, appears itself but of comparatively light account 
when placed before the massive presence of Nature and 
her argument, and hereupon we find that inquiry will 
sometimes dare to acknowledge this, and after having 
also capable of leading to some general principle. 
pondered long over the themes of unity and of variety, as 
recorded in books, will at length turn to question Nature 
herself, and ascertain of her own person how far she is 
Whether it be 
the fact that she is altogether absolutely uniform to her- 
self, or whether it be true that she is absolutely difform, 
and whether (upon finding that the absolute condition is in 
fact characterising neither the one or the other form of 
development) it may not be the operation of a law exer- 
cising upon whole quantities, and subtracting* from the same, 
that yields the result as we see it, viz., a natura, or serial 
order of forms which possesses certain parts in common, but 
which are not all equal as to quantity. If this question be 
asked of Nature herself, we shall find that she quickens 
with a ready answer in the affirmative, and demonstrates 
that her serial quantity 1 / a, fig. D, is a proportional of the 
same numerical unit, 1/a, of fig. C. And as this latter is 
evidently the serial proportional of 12 da, fig. C, which 
unit is again the proportional of 11 da, fig. C; so by serial 
natural creation, contemplated under serial mental infer- 
ence, one may regard the unit 1 Za, of fig. D, to be as the 
proportional of the thoracic quantity ll da, fig. D, by 
which comparative and combinative reading we associate 
the “anomalies”? + with the normal forms, and both with 
the common law which presides over their creation. 
And drawing our conclusions according as the anatomi- 
cal facts present themselves, we say that it is the law of 
proportioning from a plus archetype figure which renders 
figs. A, B,C, and D various to each other in respect to 
quantity only, and that the same law may be traced 
through the several conditions of the serial figure 1a, 
uniform, and in what degree she is various. 
which is at one time plus and at another time minus. 
* “But of this frame, the bearings and the ties, 
The strong connections, nice dependencies, 
Gradations just, has thy prevading soul 
Looked through ? or can a part contain the whole ?’’"—Pope, Essay on Man. 
t+ “Le temps viendra peut-étre, que l’on joindra en un corps régulier ces membres épars; et s’ils sont tels qu’on le souhaite, ils s’assembleront 
en quelque sorte d’eux-mémes, Plusieurs vérités séparées, dés qu elles sont en assez grand nombre, offrent si vivement a l’esprit leurs rapports 
et leur mutuelle dépendance, qu’il semble qu’aprés les avoir détachées par une espéce de violence les unes des autres, elles cherchent naturelle- 
ment a se réunir.”’—Fontenelle, Préface sur I’ Utilite des Sciences, Sc. 
