DIALYSIS. 69 
the same as that of the affected organ, but there are 
other examples, probably equally due to fissiparous 
division, where the new growth is either parallel to, or 
even at angle with the primary organ. Of such nature 
are some of those instances wherein two leaves appear 
to be placed back to back. These partake of the nature 
of excrescences or of exaggerated developments, and 
hence will be more fully treated of under the head of 
hypertrophy. It must be remembered that in some of 
these cases the fission may be a resumption of charac- 
ters proper to the species under natural conditions, 
but lost by cultivation or otherwise. Thus, Mr. Buck- 
man accounts for ‘“ finger-and-toe’ in root-crops on 
the principle of reversion to the wild form. 
CHAPTER ILI. 
DIALYSIS. 
Ts term is here made use of in the same sense as 
in descriptive botany, to indicate the isolation of parts 
of the same whorl; it is thus the opposite of cohesion. 
Morren, as has been previously stated, employed the 
word in a different sense, while Moquin-Tandon’ in- 
cluded cases of this description under the category of 
*‘ Disjonctions qui isolent les organes.”’ 
Dialysis, as here understood, may be the result of 
an arrest of development, in consequence of which 
parts that under ordinary circumstances would become 
fused, do not do so; or, on the other hand, it may be 
the result of an actual separation between parts primi- 
tively undivided. As it is not possible in every case to 
distinguish between the effects of these two diverse 
causes, no attempt is here made to do so. 
1 Loc, cit., p. 298. 
