48 Prof. Owen on Life and Species. 
et 4 acquérir, par un accroissement dans J’intensité des effets, — 
de plus en plus, le caractére d’ampoules et décidément de tra- 
chées, jusqua’ a ce qu’enfin survienne dans le thorax une con- 
centration des sinus respiratoires, et des arrangements de struc- | 
ture pour l’isolement des poches ou théatres de respiration, 
SABES suivant leurs qualités conditionnelles, powmons ou — 
bran 3. — 
“ee should not be dedting fairly with this exposition of trans- | 
mutative conditions if we were to take its terms in their lite- 7 
ral or usual acceptation ; else, the obvious objection that em- © 
bryos are shut out from the influence of the atmosphere until ~ 
their lungs are prepared for it, at once suggests itself. I as- 
sume, therefore, that the term is used, metaphorically, to sig- | 
nify the low and early embryo-like forms of living things. But _ 
it may cen be remarked that if speculation be permitted on | 
possible changes in the constitution of the atmosphere of this _ 
planet, during past geological eons, it is more probable that — 
the proportion of the carbonic acid has been reduced than that _ 
of the oxygen. The prevalence of remains of cold-blooded ~ 
slow-breathers in palzozoic and older mesozoic strata has more — 
than once suggested such relation to the ‘ambient medium! 
I ciety however, that the sole consequence of vague gene- 
ralities, or figurative impersonations, propounded to show how 
transmutation may go on, has been to prejudice calm and 
sound judgments against any acceptance of, or favor toward, 
the grounds of a belief in ee creational law. I have _ 
k and i 
Sane of transmutation, by reference to the species Chiromys 
ys 
Madagascariensis :* 1 will now apply Ss rae together with 
Geoffroy’s, to another and iene degree o 
What spectacle can be more beautiful, inthe ie and sugges- 
tive than that of the inhabitants of the calm expanse of water | 
careous basin out of the question, and restricting; the test 7a 
the —— cemented or otherwise confined to itsarea: we may — 
~ ae 
sposed so as to for 
i oom come intermediate lamine, g 
icles and threads, with outer folds in in arran 
bi 
fase a! P 
Were the elements of the coriaceous and of the softer contrac- 5 
snes S 
