Notes on Devonian Plants from Scotland. q 
tion somewhat obscure and there are no leaf scars or 
distinct articulations and the spiral arrangement, while 
possible, is obscure, in the latter the leaf scars and articu- 
lations are prominent, the leaf positions distinctly separated 
and the arrangement strongly spiral. To this we may 
also ad that while in Lycopodites nulleri the habit of growth 
was prostra'e in Lepidodendron gaspianum it was erect. The 
entire aspect of the two plants is quite distinct and they 
should, I think, be so considered. 
The genus Psilophyton, as described by Sir Wm. Dawson,’ 
represents again quite a distinct group of plants. Referring 
to the description of the plants upon which the genus was 
founded, [ find it to indicate ‘‘Stems branching dichoto- 
mously, and covered with interrupted ridges. Leaves rudi- 
mentary or short, rigid and pointed; in barren stems, 
numerous and spirally arranged; in fertile stems and 
branchlets sparsely scattered or absent; in decorticated 
specimens represented by minute punctate scars. Young 
branches circinate; rhizomata cylindrical, covered with 
hairs or ramenta, and having circular areoles irregularly 
disposed, giving origin to slender, cylindrical rootlets. In- 
ternal structure, an axis of scalariform vessels, surrounded 
by a cylinder of parenchymatous cells, and by an outer 
cylinder of elongated woody cells. Fructification consist- 
ing of naked, oval spore cases, borne usually in pairs on 
slender, curved pedicels, either lateral or terminal.” 
By comparison with the type specimens in the Peter 
Redpath Museum, and both with Lycopodites milleri, I find 
that there is no ground upon which the two can be properly 
identified as belonging to the same genus. Indeed, the dif- . 
ferences are even more marked than those so readily 
observable between Lycopodites and Lepidodendron. The 
interrupted ridges and circular areoles of Psilophyton as 
appear in the description above quoted, are absolutely want- 
ing in the specimens of Lycopodites in my hands. Again, 
the greater number of specimens of Psilophyton show it to 
1 Rept. Geol. Surv. Can., Foss. Plants of Dev. & Up. Sil, 1871, p. 37; Jn’l. 
Geol. Soc. XV, 478, 479 ; Can. Nat. VIII, p. 379. 
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