62 Mr. R. Kidston on British Carboniferous Lycopods. 
especially founding his opinion on the fact that Dawson 
states in the description of his species—Lepidophloios parvus 
= Sigillaria discophora—that the vascular points are obscure. 
I received, however, in 1886 from the Rev. David Lands- 
borough, Kilmarnock, to whom I am indebted for many 
instructive specimens of our Carboniferous Lycopods, a frag- 
ment of a Jarge specimen of Sigillarta discophora, which was 
unfortunately broken into several pieces when removing it 
from the roof of the Whistler Seam, Kilmarnock. This 
example shows clearly the central and two lateral cicatricules 
of the leaf-scar. A small portion of the specimen is shown in 
Pl. IV. figs. 1, La. This specimen conclusively proves that 
the leaf-scars of Sigillaria discophora, Konig, sp. (= U. minus, 
L. & H.), are provided with three cicatricules very similar to 
those of Sigillaria, in which genus I believe the plant under 
discussion should be placed. It is very remarkable that in 
such a common British Coal-measure fossil the true outer 
surface of the bark, showing the leaf-scars in a good state of 
preservation, is so seldom met with. One reason for this is 
the persistence of the leaves, which appear to have retained 
their attachment to the stem much longer than in the other 
Coal-measure Lycopods, and it is not uncommon to find the 
leaf-scars on stems of large specimens of Stgillaria disco- 
phora entirely obliterated by the foliage of the plant being 
closely adpressed to the bark. 
T united U. majus and U. minus, L. & H.; but M. Zeiller 
regards them as distinct species, and has since figured a 
specimen which he believes to be the U. majus of Lindley 
and Hutton *, with which he unites Stgi/laria (Lepidoden- 
dron) discophora, Konig. From the examination of a plaster 
cast of Kénig’s original specimen, which is still preserved in 
the collection of the British Museum, I feel quite satisfied 
that Kénig’s plant is beyond all doubt referable to U. minus, 
L. & H., and not to their U. majus, whatever may be the 
claims of Ulodendron majus, L. & H., to rank as a species. 
The size of the Ulodendroid scars or of the leaf-scars is of no 
specific value, and I have specimens of Sigillaria discophora 
in my own collection with Ulodendroid scars ranging up to 
54 inches in their greater diameter. There is no Uloden- 
droid scar on the specimen of U. majus figured by Zeiller ; 
of course this does not prove that his specimen does not 
belong to that species, but as the case stands, I at present 
believe that U. majus, L. & H., and U. minus, L. & H., are 
different ages and conditions of one species. I also feel cer- 
* ‘Flore fossile du bassin houiller de Valenciennes,’ p. 481, pl. Ixxiii. 
fig. 1. 
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