22 
On some Conditions of the Crtu-watL in the Prrats of 
Frowers, with Remarks on some so-called ExvERNAL 
Seconpary Derrosrts. By 'Turren West. 
In working over microscopic subjects generally, my atten- 
tion was arrested by that well-known object, the petal of the 
geranium, and the attempt to reconcile the appearances found 
with the descriptions in books led to investigations, some of 
the results of which are embodied in the following commu- 
nication. How far these agree with the opinions entertained 
by previous observers will best appear in the course of my 
remarks. 
It may be desirable to state at the commencement the 
mode of examination followed. Considering the soft and 
perishable nature of the structures to be determined, it 
seemed essential that they should be viewed as quickly as 
possible after being gathered, before any changes from the 
natural condition of the parts in life could have taken place. 
Some petals, as those of Clarkia, are so exceedingly delicate, 
that even the water added for their examination speedily 
renders them a confused mass, in which little is discernible 
save certain large Raphidian cells. So essential has it ap- 
peared to have the flowers freshly gathered, that I have felt 
obliged to reject some observations made on withered petals, 
lest wrinkling of the cell-wall might have been thus induced, 
and erroneous opinions formed—the serious nature of which 
will be seen as we advance. Descriptions of appearances 
brought into view in petals dried, mounted in Canada balsam, 
blistered by heat (I had almost said tortured to produce false 
appearances), cannot therefore but be viewed with distrust. 
Were anything to be gained by it, it would not be difficult 
to explain the nature of the errors induced by such modes of 
examination. 
Having then procured perfectly fresh flowers, a petal was 
detached, and bent backwards so as to expose the outline of 
the layer of cells forming the inner surface; another petal, 
bent inwards upon itself, gave the outline of the external 
surface ; the margin was next examined, and, finally, por- 
tions torn up with needles. Glycerine was found very useful 
in rendering the structures distinct, and I may mention also 
that it preserves most petals in a highly satisfactory manner. 
In the great majority of the plants examined, which 
amounted to some hundreds, when a profile view is thus 
obtained, it will be found that the cuticle is not uniformly 
level, but the cells composing it are mostly elevated towards 
the centre, more or less above the general surface. Such 
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