1048 DR R. KIDSTON, MR T. C. CANTRILL, AND MR E. E. L. DIXON. 



Sigillaria Boblayi Brongt. 



PI. IV, figs. 3 and 3a. 



1836. Sigillaria Boblayi, Brongt., Hist, d. veyet. foss., p. 446, pi. cliv. 



1857. „ ,, Goldenberg, Flora Sarsep. foss., Heft ii, p. 37, pi. x, fig. 15. 



1886. ,, ,, Zeiller, Flore foss. bassin houil. d. Valen., p. 572, pi. lxxxiii, figs. 1-3. 



1904. ,, ,, Zalessky, " Vcget. foss. du bassin du Donetz," Mem. du Comite geol. (St Piters- 



bourg), nouv. ser., livr. xiii, p. 120, pi. x, fig. 5 ; pi. xi, fig. 10 ; and text- 

 fig. 11, p. 71. 



1905. ,, ,, Koehne, in Potonie (pars), Abbild. u. Beschreib. foss. Pfta7>zen-Ileste,Liei. iii, 



No. 57, figs. 1-4. 

 1914. ,, „ Arber, Phil. Trans., ser. B, vol. cciv, p. 419, pi. xxviii, fig. 22. 



1836. Sigillaria elliptica var. (3, Brongt., Hist. d. veget.foss., vol. i, p. 447, pi. clii, figs. 1, 2. 

 1882. ,, ,, Weiss, Aus d. Sleink., p. 5, pi. i, fig. 6 (Zweiter Abdruck). 



1881. Sigillaria hexagonalis, Achepohl, Niederrh. Westfdl. Steinlc., p. 72, pi. xxi, fig. 10. 

 1879. Sigillaria mamillaris, Lesqx. (non Brongt.) (pars), Coal Flora, p. 483, pi. Ixxii, fig. 6. 

 1912. Sigillaria trigona, Arber (non Sternb.), Phil. Travs. ser. B, vol. ccii, p. 253, pi. xii, fig. 11. 



Description. — Stem ribbed, ribs straight or slightly undulating. Leaf scars distant, 

 but sometimes only separated by a space of not more than from ^ to ^ their own 

 length, and occupying from ^ to f the width of the rib, hexagonal or hexagonal- 

 pyriform, upper half contracted with somewhat concave sides, flattened and slightly 

 emarginate at top ; basal portion of scar rounded, with frequently two blunt points 

 where the sides join the more flattened base, and from which occasionally two short 

 divergent ridges are given off. Lateral angles pointed, prominent, and give rise to 

 two diverging lines which speedily reach the furrow, where they die out. Cicatricules 

 situated about tj the length of the scar from its upper margin, central punctiform, 

 and in a line with the centre of the two lateral straight or lunate cicatricules. 

 Immediately above the leaf scar is the ligule pit, and a short distance above it is a 

 transverse furrow which occupies about half the width of the rib. 



Between the transverse furrow and the summit of the leaf scar, the cortex is 

 ornamented with short, bent, transverse ridges ; and extending from the base of the 

 leaf scar to the furrow is a broad band of strongly marked, short somewhat irregular 

 transverse ridges ; marginal areas of ribs smooth or faintly striated. 



" Cone scars borne at the edge of the ribs close to the furrows, forming a band 

 round the stem, irregularly placed, rounded or elliptical, sometimes deformed and 

 polygonal, 5 to 10 mm. long and 4 to 5 mm. broad, having in the centre a strongly 

 marked cicatrice, and deforming the leaf scars among which they are placed " 

 (Zeiller). 



Sub-cortical surface of stem strongly striated longitudinally. 



Remarks. — Though the distance of the leaf scars in this species varies somewhat, 

 they never seem to be quite so far apart as the length of a leaf scar, and are usually 

 much closer. 



When the leaf scar is fully exposed, the lateral angles are very prominent ; but 



