Notes . 
601 
ON SOME NEW FEATURES IN RELATION TO LYGINO- 
DENDRON OLDHAMIUM h — Since the year 1872, when the late 
Dr. W. C. Williamson published his memoir, part iv, in the c Phil. 
Trans. Roy. Soc.’ on Diciyoxylon, Lyginodendron and Heteran - 
gium , this genus of fossil plants has undergone a good many alterations 
or modifications at the hands of the palaeobotanist. 
In the memoir above quoted Lyginodendron oldhamium is described 
as an unbifurcating stem, but giving off very small branches (see 
p. 387, Figs. 14 and 16, PI. XXV, loc. cit.), and in some respects 
similar to a Lepidodendroid stem. 
In his memoir, part vi, 1874, he describes fully a stem to which he 
originally gave the name of Edraxylon, but to which he now gave the 
name of Rachiopteris aspera. (See Figs. 1 to 13, ‘Phil. Trans. Roy. 
Soc./ 1874, part vi. Fig. 13 he describes as a petiole with pinnules 
and leaflets.) 
In memoir, part vii, 1875, he describes a series of specimens under 
the name of Kaloxylon Hooheri . (See Figs. 23 to 38, PI. 5, 6, and 7, 
loc. cit.) 
The small branches which Williamson described in 1872 ryider the 
name of Kaloxylon have since been proved to be the roots of 
Lyginodendron. 
In the case of Rachiopteris aspera , it is now well known that it is 
the leaf-stalk or petiole of Lyginodendron , whilst the fossils known as 
Sphenopteris Honinghausi and Sphenopteris distans are the foliage of 
Lyginodendron. (See Williamson’s memoir, 1890, part xvii; also 
Williamson’s and Scott’s memoir, Phil. Trans. Roy. Soc. 1895, 
part iii). 
In most cases when this stem has been described it is as an unbi- 
furcating or unbranching stem. 
In Dr. D. H. Scott’s ‘Studies in Fossil Botany,’ p. 321, he says 
that ‘ No stem has ever been observed to branch ; it does not follow 
that it never did so, but branching must have been very rare.’ For 
some time back I have had various specimens in my possession 
which I have collected from Dulesgate, near Todmorden, Lancashire, 
which to me have had the appearance of giving off a branch ; but 
during the last few months I have discovered two specimens which 
1 Abstract of paper read before Section K of the British Association, Belfast, 
1902. 
