BY MOLECULAR COALESCENCE. 73 
living tissues, may, like shell, have life, and with it the 
power of growth or development; the secretion serving 
as the blastema or pabulum from which the cell- 
contents are derived. Professor Quekett adds, that he 
would not assert positively that such is the case, but 
when the subject is carefully considered, ‘it has the 
appearance of truth on its side.” I may observe that by 
this allusion to Mr. Quekett’s lecture, I do not necessarily 
refer to him as the originator of these views, whether they 
be true or false, but I have merely quoted this lecture as 
showing his opinion upon this subject, an opinion which, 
from Mr. Quekett’s high position and very extensive know- 
ledge of histology, I consider to be the one most generally 
entertained, at least in this country, where the cytoblast 
theory of Schwann is carried to its greatest extent. 
Now it may be observed, that as these calculi are formed, 
as Mr. Quekett has noticed, in connexion with the body, 
or at any rate they are found in a fluid which has pro- 
ceeded directly from the blood, it is impossible to prove 
that they are not of vital origin. The cell theory is 
altogether in favour of this view; for nothing can appear 
more probable than that a cell-germ, having escaped from 
the blood into the pelvis of the kidney, should afterwards 
be carried with the urine into the bladder, where, in- 
creasing and multiplying by the exercise of its own 
inherent vitality, it should grow, at the expense of the 
secretion containing it—this serving as its blastema—into a 
calculus; hence this question, like most other pathological 
and physiological ones, can only be decided by the com- 
parison of evidence adduced on both sides. As in the 
discussion of this and other questions I shall frequently 
be obliged to refer to the cell-germ theory, I think my 
observations will be better understood if I at once 
