THE INTERNAL STRUCTURE OF SIGILLARIA ELEGANS. 535 
le Sigillaria spinulosa” * that any real advance was made in our knowledge of the 
structure of Sigillarian stems. This important memoir is a worthy companion to 
Bronenrart’s “ Observations,” and is one of the most valuable contributions which 
have been made to the subject. 
Sigillaria spinulosa, Rost, sp., is the Leiodermarian condition of Sigillaria Brardi, 
Brongt., and is the type of the section Lesodermaria. Probably there are species 
of Sigillaria which possess a Leiodermarian type of cortex in all stages of their 
growth, but unfortunately the internal structure of none of these is known. 
RENAULT gives some additional details of the structure of Sigillaria (Clathraria) 
Menardi, Bronet., and Sigillaria (Leiodermaria) spinulosa, Rost, sp., in the Bassin 
houiller et permien d’Autun et d’Epinact and also in the same work describes a 
Sigillarian axis under the name of Stgillaria xylina. { 
All the Sigillarian specimens whose structure was known previous to 1899 belonged 
to the non-ribbed members of the genus, but in that year Professor BERTRAND read an 
account of a ribbed Sigillaria (S. elongata, Brongt.) before the Botanical Section 
of the British Association at Dover. An abstract of this communication appears 
in the Annals of Botany, vol. xiii, 1899, p. 607. This paper gives the first clear 
account of the structure of a mbbed Sigillaria, and embraces all we know of the 
structure of this group, with the exception of a short account given by Dr Scorr 
of a transverse section of a Sigillaria (Rhytidolepis) type, § and a note by WILLIAMSON, || 
with a few explanatory remarks, where he refers the Diploxylen of his Memoir II. 
to Sigillaria reniformis, Brongt. 1 This identification by WiLLIaMson is improbable, 
as Sigillaria reniformis has never, as far as | am aware, been found in so low a 
horizon as that from which WILLIAMSoN’s specimen came—the Lower Coal Measures. 
The above brief sketch contains a note of the papers and works dealing with 
original investigations on the structure of undoubted stems of Szgzllaria as far as known 
to me,** but before passing from the literature of this subject I wish to refer to a stem 
which has been described by Professor F. E. Weiss as “‘a biseriate Halonial branch of 
Lepidophloios fuliginosus,” t+ and which I think more probably belongs to the 
Ulodendroid group of Clathrarian Sigillaria than to Lepidophlovs. I have come to 
* Mem. présentés par divers savants a ]’Acad. des Sciences de l’institut national de France, vol. xxii., No. 9, 1875, 
Paris, pls. i—iv., pl. vi. figs. 33, 34. See also Renavtt, “Structure comparée de quelques tiges de la flore carbonifére,” 
p- 264, pl. xi. figs. 17-21, pl. xii. figs. 1, 2, 1879. “Notice sur les travaux scientifiques de M. Bernarp RENAULT,” 
Autun, 1896, p. 132. 
+ Fase. iv. part ii., 1896, pp. 200, 208, pl. xxxvi. figs. 8-11, pl. xxxvii. figs. 3-7 and fig. 40 (Sig. Menardi), pl. xxxvi- 
figs. 2-5, pl. xli. figs. 4-11, 18-21, 23-26 (S. spinulosa). 
t Lc, p. 237, pl. xxxviii. figs.1-3. § Studies in Fossil Botany, p. 207, fig. 80, 1900. 
|| General, Morphological, and Histological Index to the Author’s Collective Memoirs on the Fossil Plants uf the Coal 
Measures. Part I]. Mem. and Proc. Manchester Lit. and Phil. Soc., Session 1892-93, p. 35, 1893. 
| Pl. xxviii. figs. 33, 34. 
_ ** See, in addition to references already given, RENAULT, Cours d. botan. fossile, vol. ii., 1881. Poronih, Lehrbuch 
der Pflanzenpaleontologie, 1899. Zer~LER, Eléments de Paléobotanique, 1900. Soums-LavBacu, Fossil Botany (English 
translation), Oxford, 1891. Kupston, “Carboniferous Lycopods and Sphenophylls,” Trans. Nat. Hist. Soc. Glasgow, 
vol. vi., new series, p. 101, 1891. 
tt Weiss, Trans. Linn. Soc. London, 2nd ser., Bot., vol. vi. part 4, pp. 217-236, pls. xxiii.—xxvi., 1903. 
