SALTER — A CHRISTMAS LECTURE ON COAL, 
127 
Lepidodendron differed from Sigillaria in the arra-ngement of the 
leaf-scars, which pack closely in quincunx fashion over the surface. 
Our sketch shows this. The patterns are equally beautiful and as 
applicable to pictorial design as in the other case. The diamond 
shape of the scars will help you easily to recognise fragments. 
There are many species of these trees. The commonest of all I think 
is the L. Sternhergii, of which a full length figure is to be found in 
the revised edition of Dr. Mantell's excellent book — " Jones's Won- 
ders," as it ought to be called — p. 749. I have only given you frag- 
ments of branches, stems, leaves, fruit cones and their seeds or 
Stem ("aj, and leaves, catkin (b), seed-vessels (c), and seeds or spores fdj of Lepidodendron. 
We have added CeJ its supposed root Halonia. 
spores. It is well known now that Lepidostrobus (h) is the 
fruit or catkin ot Lepidodendron. The little mountain club- 
moss, which rears its yellow catkins amid the sheltering boughs 
of the heather, — its stem clothed with long scale-like leaves, — 
is the best representative, in England at least, of these old giant 
forms, as large as forest-trees, which abounded so gi-eatly in the 
times of the coal. 
There is yet another plant, so very common in coal- shales, that it 
ought to be mentioned separately. I mean the Calamites. We have 
not space for a figure, and refer you to the book above quoted, p. 
736, where the plant is, however, drawn upside down in fig. 3 — quite 
right in figs 1 and 2. The look of these plants is so much that of the 
horsetail (Equisetum) of our ditches, that it is no wonder ordinary 
fossil-hunters should take them for blood-relations. 
* And I have added the Halonia^ which I fully beUeve to be the root of 
Lepidodendron. 
