262 THE WINTER STATE OF OUR DUCKWEEDS. 
be, or how far they had advanced in laying the rudiments of the 
organs possessed by the mature frond. Here began the difficulties 
of the investigation. My desire was to trace back the frond to the 
stage in which it was represented by a single cell, or at least by a 
small group of homogeneous cells, on which there was no sign of 
any organ ; and then to be able to see both where and in what shape 
each new part was produced by changes in the growing point and 
the tissue adjacent thereto. 
Of the two budlets, the one on the left, next to the main stem, 
was the most developed, and I studied it, rather than the other. 
Figs. 6 and 14 present the views obtained when the razor just 
- grazes the upper surface of the buds. Near the upper edge of the 
bud was a most delicate line, Fig. 6 m, which could hardly be traced 
with aj inch objective. A 4 objective and 1, objective showed 
that it was the edge of a membrane consisting only of one layer of 
cells in thickness. The cells, Fig. 55, were irregularly shaped and 
had crinkled walls. I could follow the line most to the edges of 
the bud, but not quite. The budlet, Fig. 14, was, like the bud, of a 
rectangular outline nearly, and grew out from the corner of its 
cavity. I could make out the following particulars ; “a” a fine 
curved line which it took close observation to see at all; “d” a 
double line at the back of the budlet ; “ c” and “ e” two swellings 
of the outline of the budlet “5;” “f” an edge of tissue two cells 
thick coming to a point where it reached the frond at “i;” “h?” 
the least developed budlet ; and “g” a small protuberance of cells, | 
which I have not thoroughly studied and shall therefore be obliged n 
to omit in my descriptions. What it may grow into, if it grow at i 
all, I cannot say. a 
Horizontal sections had helped greatly, but vertical sections 
seemed now to offer the only hope of i increasing my knowledge of 
the bud and budlet. After making many, I was no better off, be- 
cause it was impossible to tell exactly in what direction, as regards 
the axis of the bud, the sections went. I then split a frond through 
so as to reveal the upper surface of the bud r touching it 
with the razor or loosening it from its attachmen 
Then with the camera I sketched its Sens as seen with a 
and was then ready for the delicate work of slicing it up. (Fig. 7 
_ gives such an outline.) Taking the frond on the forefinger I cut 
one section as nearly as possible in the direction which I had 
— decided would give a longitudinal section of the bud, as Fig. 7 e-e- 
a 
m 
: 
id ces N Se 
Be EERE 
