1893.] The Roots of Ranunculacee. 97 
A comparative study of the roots of Ranunculacee. 
FRED. B. MAXWELL. 
WITH PLATES II—IV. 
(Continued from p, 47.) 
V. A study of the meristem. 
In the studies thus far made, the roots of Ranunculacee 
have all been assigned to one type, as regards their apical 
meristem structure, this being Erickson’s third type and Janc- 
zewski’s fourth. My investigations indicate that the roots 
do not all follow this type, some agreeing with Janczewski’s 
third type, and on account of a modification of structure for 
ne species, I have provisionally formed another subsidiary 
y 
pe. 
I have not thought it necessary to describe and figure the 
meristem of each particular species, but will define the type, 
describe one representative species under it and then name 
the other species found to agree with this type. 
si ly first type includes roots having three primary meri- 
ass a” the plerome, the periblem, and, in Erickson’s 
via a € dermocalyptrogen, the root-cap and epidermis 
ski's be aeli origin. This will be seen to be Janczew- 
dicotyled ype, Corresponding to Erickson’s first type for 
me ons. As an example of this type I describe the 
ure of the root tip of Ranunculus sceleratus.1 In this 
is Can be traced from above the root-cap, 
eneath its layers, and ending as a distinct 
near the tip of the central cylinder, as shown 
: at this point the cells lose their epidermal 
and merge into the tissue of the root-cap; 
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tip, though here it is reduced to about two 
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Species found to agree with this in structu ee 
tus, R. aquatilis var. trichophyllus, Clematis 
: Iv, fig. 30. 
