198 LYCOPODIALES [CH. 



out, with Euphorhites vulgaris of Artis and with the plant after- 

 wards figured by Brongniart as S. pachyderma^. Brongniart in 

 1822 figured another type of stem characterised by the absence 

 of ribs and by prominent spirally arranged cushions bearing 

 relatively large leaf-scars like the upper part of the specimen 

 shown in fig. 203 ; this he named Clathraria Brardii, a well- 

 known and widely distributed Carboniferous and Permian species 

 now spoken of as Sigillaria Brardi (figs. 196, A — C ; 203). A 

 third type of stem figured by Brongniart as Syringodendron 

 striatum^ agrees with Sigillaria scutellata in having ribs, but 

 differs in the substitution of narrow oval ridges or depressions 

 for leaf-scars ; this is now recognised as a partially decorticated 

 Sigillaria, in which the vascular bundle of each 'leaf is repre- 

 sented by a narrow ridge or depression. The name Syringo- 

 dendron, originally used by Sternberg, is conveniently applied 

 to certain forms of Sigillarian stems which have lost their 

 superficial tissues. A fourth generic name, Favularia, was 

 instituted by Sternberg' for Sigillarian stems with ribs covered 

 with contiguous leaf-scars of hexagonal form and prominent 

 lateral angles (fig. 193, A ; fig. 200, G). 



The generic or subgeneric title Rhytidolepis, also instituted 

 by Sternberg, is applied to ribbed Sigillarian stems such as 

 S. scutellata, 8. rugosa (fig. 193, B), 8. mammillaris (fig. 195), or 

 S. laevigata (fig. 196, D). Goldenberg* proposed the name 

 Leiodermaria for smooth Sigillarian stems with leaf-scars not 

 in contact with one another (fig. 196, C). 



The shoot system of Sigillaria consisted of a stout stem 

 tapering upwards to a height 9f 100 feet' or more as an un- 

 branched column, with its dome-shaped apex* covered with 

 linear grass-like leaves or, in some species, such as Sigillaria 

 Brardi'', 8. Eugenii^, etc., the main trunk was occasionally divided 

 by apparently equal dichotomy. The younger portions of the 

 stem or branches were in some species clothed with leaves 

 separated by a narrow zigzag groove surrounding their hexa- 



1 Brongniart (37) PI. cl. fig. 1. 



2 Brongniart (22) A. PI. xii. figii 3. 



3 Sternberg (23) A. * Goldenberg (-55). 

 = Zeiller (88) A. (S. elegans). « Goldenberg (55). 



' Eenanlt (96) A. PI. xxxv. s gtur (75) u. A. PL xwi. 



