226 LYCOPODIALES [CH. XVI 



outline, — the lateral angles pointed and transversely elongated, 

 the upper and lower angles rounded, — bear three scars, the 

 central leaf-trace and two straight or curved lateral parichnos 

 scars ; a ligular pit occurs immediately above the centre of the 

 upper edge of the leaf-scar and occasionally circular elevations 

 with a central pit occur singly or in pairs below a leaf-scar 

 (fig. 196, A). The linear leaves, which may persist on shoots 

 having a fairly large diameter^ have a single median vein and 

 two stomatal grooves on the lower surface ^ (fig. 200, D). 



Partially decorticated and younger shoots are characterised 

 by the occurrence of pairs of elliptical parichnos areas and a 

 smaller median leaf-trace scar. The surface of older stems, 

 which may show signs of longitudinal splitting {Syringodendron 

 state), bears pairs of parichnos scars reaching a length of 

 2 — 2"5 cm. and a breadth of 10 — 13 mm. The regularity of the 

 leaf-scar arrangement is interrupted at intervals by the occur- 

 rence of more or less regular verticils of scars marking the 

 position of deciduous shoots. Grand'Eury' has figured cones 

 which he believes to be those of this species, and Zeiller refers 

 the large strobili, Sigillariostrohus major, to Sigillaria Brardi*. 



The subterranean axes were characterised by spirally disposed 

 rootlet-scars like those of Stigmaria ficoides (figs. 204, 205) and 

 by a cortical surface with the features of Stigmaria rimosa Gold.' 



The anatomy of the stele and leaves has already been 

 described (p. 219). The stele of the Stigmarian portion of the 

 plant consists of a band of centripetal primary xylem and a 

 cylinder of centrifugally formed secondary wood with medullary 

 rays containing vascular bundles passing out to the rootlets"- 



Sigillaria Brardi occurs not uncommonly in Permian rocks ; 

 it is recorded from France', Germany", Pennsylvania', and 

 elsewhere. It is found in the Upper, Middle, and Lower 

 Coal-Measures of England^" and in Permo-Carboniferous strata 

 in Africa" and Brazil^^ 



1 Zeiller (06) PI. xlii. ^ Benault (96) A. Pis. xxxvii. xli. 



3 Grand'Eury (90) A. PI. xi. ^ Zeiller (06) p. 176. 



6 Goldenberg (55) PI. xii. « Benault (96) A. PI. xxxix. 



' Zeiller (92) A.; (06). » Potonie (96) A. " Fontaine and White (80). 



i» Kidston (94) p. 252. " Seward (97^) A. 



12 White (08) p. 450, PI. v. fig. 12. 



