1893. | The Roots of Ranunculacee. 43 
this class I would also include Hepatica acutiloba,’ Hi. triloba, 
Aconitum Noveboracense,? Trollius laxus, Caltha palustris, 
Ranunculus recurvatus, R. Pennsylvanicus, R. fascicularis,® 
R. ctrcinatus,® R. aquatilis var. trichophyllus,? R. bulbosus, R. 
multifidus,* R. septentrionalis, and R. hispidus Michx.,® aform 
not recognized as a distinct species in Gray’s Manual, but it is 
certainly a very distinct type and I believe is recognized as a 
species by many botanists, though others regard it as a variety 
of RK. fascicularts or R. septentrionalis. In root structure it is 
more like the latter. In all of these species which I could 
get to study, the roots, both young and old, large and small, 
had the characteristic radial type of root structure. In certain 
cases it might be that at another time of the year the roots 
would have presented a different structure, though as most 
of my material was collected in the fall the larger roots col- 
lected then ought to have shown it, if there was to be a 
change through secondary growth. 
The second class on this basis would include those plants 
in which, by the growth of secondary xylem rays between the 
primary ones and in front of the phloem masses (these second- 
ary rays often becoming more prominent than the primary 
ones), the radial character of the young root is lost and the 
bundle appears like a collateral one with the xylem collected 
in the center and the phloem in separated groups answering 
to the original number of the xylem rays, and lying entirely 
without the xylem mass. Along with the change in. the 
bundle area the endodermis generally undergoes a change. 
Through division the cells become much smaller and often 
nearly square in form; and the whole central cylinder becomes 
lar ger in proportion to the diameter of the root, partly through 
increase in bundle elements and partly through increase of 
conjunctive parenchyma. On the other hand many of the 
roots of the first class show a smaller central cylinder in the 
older roots, the increase principally having taken place in the 
cortex. 
As a good example of this second class of roots, I will des- 
