On Sigillaria Brardii and vts Variations. 233 
XVII. On Sigillaria Brardii, Brongt., and its Variations, By 
R. Kipston, F.R.S.E., F.G.S. [Plate VII] 
(Read 15th April 1896.) 
The genus Sigilaria has usually been divided into three, 
though sometimes into four groups or sections, according to 
the value placed on the characters derived from the structure 
of the bark and the arrangement of the leaf-scars, 
I. Clathraria, Brongniart. Stem not ribbed. Leaf-scars 
placed upon more or less prominent contiguous 
rhomboidal cushions, which are separated from 
each other on all sides by well-defined furrows.! 
Type—Sigillaria Brardiz, Brongt. 
Il. Leiodermaria, Goldenberg. Stem not ribbed. Bark 
smooth, and generally ornamented with fine irregular 
longitudinal lines and finer transverse strize. Leaf- 
scars distant, not placed on prominent cushions. 
Type.—Sigilaria spvvulosa, Germar. 
III. Lhytidolepis, Sternberg. Stems bearing prominent 
vertical ribs, on which are placed the more or 
less distant leaf-scars. Z'ype.—Sigillaria scutellata, 
Bronegt. 
1V. Favularia, Sternberg. This is derived from forms 
included in Section III. The stem is ribbed, and 
the leaf-scars are placed close together, separated 
by transverse furrows, and occupy the greater 
portion of the rib. The ribs are thus more or less 
divided into sub-hexagonal areas, the lateral angles 
of which alternate with those on the neighbouring 
ribs, and thus impart to the longitudinal furrows 
a more or less zig-zag course. Z'ype.—Sigillaria 
elegans, Sternb. sp. 
The first three sections are those which have been most 
generally employed. 
In 1888 Weiss announced that from the examination of 
a fine series of specimens from Wettin, it was shown thut 
1 Weiss has substituted the term Cuncellata for this group. See Foss. Flora 
d, jungst. Stk. u. d. Rothl., p. 158, 1871. 
