APPENDIX. 
Sigillaria and Stigmaria, p. 9. 
SINCE my remarks on these fossils were written, my attention has been drawn to a paper by Mr. Richard 
Brown, entitled ‘Description of erect Stgillarie with conical Tap-roots, found in the Roof of the Sydney 
Main Coal, in the Island of Cape Breton,’ (Quarterly Journal of the Geological Society, vol. v, part 1, 
pp. 354-360,) which completely sets at rest the question as to Stigmaria being the root of Sigillaria. The 
evidence adduced by Mr. Brown is quite conclusive ; inasmuch as he describes a stem, evidently a Sigillaria, 
still attached to its root, which is clearly a Stigmaria. It does not appear that Mr. Brown has read my 
‘ Contributions towards establishing the general Characters of the Fossil Plants of the genus Sigillaria,’ or 
he would have seen, that it contained a complete demonstration of the ‘ Dome-shaped Fossil’ described in 
the ‘Fossil Flora,’ being no other than a root. The fossil roots, which Mr. Brown notices in his paper, 
have the underside of their base “divided into four equal quarters by deep channels running from near the 
centre, &c.” (p. 357.) In my ‘ Contributions,’ specimens of Stigmarza are noticed, displaying two furrows, 
or ridges (depending on whether the specimens were the fossils themselves, or merely their impressions) 
crossing each other, dividing them into four nearly equal quarters. As regards the cause of these furrows, 
or impressions, Mr. Brown’s observations have completely explained it; and I now perceive, that my opinion 
on this point is altogether incorrect. 
Allusion is made in my paper to the quincuncial arrangement of the fibrils of Stigmaria opposing the 
view of its being a root:»M. Brongniart, however, in noticing the same objection, states, that a similar 
arrangement prevails “rather often in the roots of aquatic plants,’ but without naming the species. By 
repeatedly endeavouring to find out plants having their fibrils thus characterised, I have at least ascertained, 
that the roots of the common I7is Pseudo-Acorus, when deprived of their fibrils, show the scars to be as 
distinctly arranged in quincunx as those of Stigmaria ficoides. 
Actinaria, p. 21. 
Several years since, I found in Whitley Quarry a branched Coral, about three inches long, resembling 
a Lithodendron. ‘The specimen has been lost; and I have never been able to find another of the same kind. 
Fenestellide, pp. 37, 40. 
I have lately ascertained, that Professor Oldham has anticipated me in the discovery of the root-like 
processes which are attached to the ribs or stems of this family. (Vide Journal of the Geological Society of 
Dublin, vol. 111, part i, pp. 190-193, plate 3.) 
