1893. ] The Roots of Ranunculacee. 15 
Having had access only to reviews of many of the earlier 
articles referred to in this paper, I cannot say whether some 
of them may not have worked upon this group, but the titles 
of their papers would indicate that many of them had not 
done so. Of the more important articles which I reviewed 
I find that neither Van Tieghem nor Janczewski appears to 
have included any of the Ranunculacee in their studies. 
Erickson, as already referred to, studied the roots of several 
of the Ranunculacee, among them being Ranunculus repens, 
of which he gives a figure of the meristem, and Ca/tha pa- 
ustr¢s. Flahault, in his article published in 1878, refers to 
the structure of the roots of several of this order, and he 
agrees with Erickson that the tissues merge into one at_the 
vegetative point, but would say that this was but a modifica- 
tion of the general type for dicotyledons. He figured the 
root tip of Peonia officinalis and Aconitum pyrenaicum. He- 
gelmaier, in an article on the growth of the embryo in dicoty- 
ledons, treats at length of several Ranunculacee, but gives 
slight reference to the root structure, and does not dwell on 
the meristem of the growing-point. Olivier?‘ treats mainly 
of the histological structure of roots and places Ranunculaceae 
in a class of plants in which the secondary vascular tissue ap- 
pears very late, adding that in the roots of the genus Ranun- 
culus there is less secondary vascular development than in any 
other dicotyledon. He says of the genus Thalictrum that 
the secondary growth appears late,. and but very little devel- 
oped, that the cortical parenchyma is often nearly all exfoli- 
ated, the endodermis being persistent and then serving the 
purpose of an epidermis. De Bary discusses the root struct- 
ure of several of the Ranunculace@, and gives figures of the 
cross-section of the root of Ranunculus fluitans and R. repens. 
P. Marie?®> gives an important article on the histological 
structure of Ranunculacee, referring to the general histologi- 
cal structure of the roots as well as to that of the stem, etc., but 
he does not refer to the meristem structure. He gives many 
good figures of root structure. 
Prof. Hargitt?® published a short article in the BOTANICAL 
GAZETTE, in which he describes the structure of the roots of 
lsopyrum biternatum. 
**Recherches sur l'appareil tegumentaire des racines. Ann. des Sci. Nat. 
VI. 1. 
*5Recherct ur la structure des Ranonculacees, Ann. des Sci. Nat. VI. xx. 
*SBotan. GazettE xv (1890). 235. 
