352 KiDSTOx : the flora of the carboniferous period. 
I — ( 
^ . 0 ' 
The Bothrodendra, in the characters they possess, seem to hold an 
intermediate position between the Lepidodendra and the Sigillariae. 
IV.— SlGILLARIE^. 
Sigillaria Brongniart. Arborescent Lycopods, with cactus- 
like or columnar trunks, or very sparingly dichotomously branched 
stems. The bark is longitudinally ribbed or smooth. The hexagonal 
leaf-scars are contiguous. Text Fig. 7, or distant with more or less 
rounded angles, the two 
lateral angles being most 
prominently developed, 
Text Fig. 8. Within the leaf- 
scar are three cicatricules, 
of which the central is 
punctiform, transversely 
elongate, or sub-triangular; 
the two lateral are up- 
right, and either straight 
or lunate, and larger than 
the central vascular scar. 
The leaf-scar is frequently 
placed on a more or less 
prominent elevation, which 
in the case of the ribbed 
Sigillarice slopes down- 
wards from the leaf-scar. 
Immediately above the leaf- 
scar a small cicatricule is 
frequently present. Sub- 
lateral vertical, large and 
° 
Fig. 8. — SiyiUaria priucipis Weiss. Old 
Mills Pit, Farnngton-Guniey, Somerset. 
Hor. Lower Series of the Upper Coal 
Measures. A, natural size ; B, leaf-scar 
enlarged ; a, area of scar ; h, cicatrice of 
vascular bundle ; c c, parichnos ; d, 
"ligule" scar. (No. 421.) 
epidermal cicatrices, three ; the two 
lunate, or straight, and united in the centre by the circular or 
oblong vascular scar ; or two through the obliteration of the 
central scar. They attain considerable size on old stems and, through 
coalescence, sometimes appear as one large scar. The sub-epidermal 
surface is longitudinally striated. 
The leaves are single-nerved, linear lanceolate, or long and 
grass-like. 
