— 459 — 
tudinal direction, and very often they are crescentric, tending to em- 
brace the nerve irace. In the partially decorticated stems, especially 
those of Rhytidolepis, the casts of the two lateral cicatricules are 
often very large and conspicuous The Sigillarwan leaves are rigid, 
grasslike and long, sometimes a meter or morein length. Their stru- 
ctureis much the same as in the leaves of Lepidodendron. 
The cones of Sigillarva (Sigilliariostrobus) resemble Lepisdos- 
trobus, and are borne cn long, laterally attached, peduncles. They are 
heterosporous. The root of the trees of this genus included under 
the name Stigmaria. 
The surface of a small root, from which the slender rootlets 
have fallen is very closely comparable to that of the fragment of 
Lycopodiopsis Derbyi Ren.,shown on PI. V, Fig. Il. In fact I should 
have placed this specimen in the Stigmarian group but for the ana- 
tomical details brought out by Renault and Zeiller. The internal consti- 
‘tution of the Sigilliarian wood offers no constant criteria by which 
to distinguish it from that of Lepidodendron, and it is possible that 
the fragment described on a latter page as Sigillaria? muralis really 
belongs to the other genus. 
The Rhytidolepis section of Sigillaria, is known from rocks as old 
as the Upper Devonian; but the genus, as a whole, is especially cha- 
racteristic of the Upper Carboniferous, where it is most abundant in 
the lower and middle Coal Measures. Sigillaria is rare in the Per- 
mian. A species, whose generic identity is slightly open to question, 
has been described from the Trias. The type from Brasil which I 
shall describe as Sigillaria australis approaches the latter in some 
of its characters. 
Sigilaria Brardi Brongn. 
Pl. V, Fig. 412. 
1822. Clathraria Brardit Brongniart, Mem. mus. hist. 
nat., vol. viii, pp. 209, 222, pl. i, fig 5. 
1826. Favularia Brardii (Brongn.) Sternberg, Versuch FI. 
Vorwelt., vol. 1, Tent., xiv. 
1828. Sigillria Brardii Brongniart, Prodrome, p. 65 ; Bron- 
gniart, Hist. Veg. foss. 1836, p. 430, pl. clvili, fig, 4 ; Germar, 
Verst. Steink. Wettin u. Lobejun, 1845, p. 29, pl. xi, figs. 1,25 
