On Sigillaria Brardii and vs Variations. 245 
circular scars on the Sigillaria spinulosa form, are likewise 
cone-scars. Morphologically there appears to be nothing 
by which they can be distinguished from the corresponding 
scars on the Sigillaria Brardii condition of the species. 
Only in one they occur on the Clathrarian form, and in the 
other, on the Leiodermarian condition of the plant. 
Weiss and Sterzel! suggest that Palmuacites quadrangulatus, 
Schloth. might belong to their Sigillaria mutans forma 
Wettinensis, Weiss,? and Potonié* unites it with Sigillaria 
Lrardvi, and names the specimen figured by Zeiller as 
Sigillaria quadrangulata> Schloth. sp., Sigillaria Zeilleri, 
Potonié. 
The original figure of Palmacites quadrangulatus, Schloth., 
is very obscure, and devoid of the necessary characters for 
a right knowledge of his plant; and if the figure correctly 
represents the true condition of the fossil, it must have 
been in a most imperfect state of preservation. Under these 
circumstances, I do not see on what grounds a satisfactory 
identification of Sigillaria Brardw can be made with Palma- 
cites quadrangulatus, Schloth. Such an identification must 
infer that Schlotheim’s specimen possessed characters neither 
shown in the figure nor referred to in the text, and this course 
I am not prepared to follow. But whatever view may be 
taken of Schlotheim’s Palmacites quadrangulatus, Zeiller’s 
Sigillaria quadrangulata seems to be specifically ae 
from Sigillaria Brardw, Bronegt. 
Sigillaria obliqua, Brongt.,° Sigillaria venosa, Brongt.,’ and 
Sigillaria lepidodendrifolia, Brongt. (in part),® seem to have 
very close affinity with Sigillaria Brardi, if they are really 
specifically distinct; but an examination of the original 
specimens would almost be necessary before arriving at a 
satisfactory opinion on this point. 
1 DieSigillarien d. preuss. Steink. -u. - Rothl.-Gebiete, ii., pp. 127and 237, 1893. 
2 Petrefactenkunde, p. 395, pl. xviii., fig. 1, 1820. 
3 Tbid., pl. xii., fig. 55. 
4 Flora d. Rothl. v. Thiiringen, p. 190, 1890. 
5 Bull. Soc. géol. d. France, 3° sér., vol. xiii., pl. ix., figs. 3, 4, 1884. 
6 Hist. d. végét. foss., p. 429, pl. clvii., figs. 1, 2. 
7 Tbid., p. 424, pl. elvii., fig. 6. 
8 Tbid., p. 426, pl. elxi., fig. 3 (not figs, 1, 2). 
