96 Proceedings of the Royal Physical Society. 



this has confirmed my opinion that Cyclostigma should be 

 merged in Bothroclenclron. 



The fructification of the Coal-measure Bothrodendra is but 

 imperfectly known, and, so far as I am aware, the only cone 

 identified with the Coal-measure members of the genus is 

 that with short bracts figured in this communication. The 

 cones, however, of the Cyclostigma kiltorhense are provided 

 with long, linear, lanceolate bracts with a subtriangular base, 

 on which the spores are borne. These have been figured by 

 Schimper as Zepidostrohus Bailyanus} Their w^hole struc- 

 ture reminds one much of Sigillarian cones. 



At present so little is known about the fructification of 

 the various species of Bothrodendron, that on this important 

 point a comparison cannot be made between the members 

 of the genus ; but so long as the generic characters of 

 these Lycopods are founded on the structure of the leaf- 

 scar, Cyclostigma must be enrolled in the older genus 

 Bothrodendron. 



I am aware that the description of the leaf-scar of Cyclo- 

 stigma that I now give, differs in some important points 

 from that given by Dr Haughton^ and by Heer,^ as also 

 from the figures and descriptions given by this last-mentioned 

 author in his " Fossile Flora der Baren Insel ; " but in many 

 of the specimens a certain amount of shrinkage appears to 

 have taken place, w^hich may have reduced the leaf-scars to 

 the condition in which many of them occur. Be this as it 

 may, the fact remains that when well-preserved examples 

 are examined, it is found that the leaf-scars of Cyclostigma 

 contain three cicatricules similar to those of Bothrodendron. 



Explanation of Plate. 



Fig. 1. Sigillaria discophora, Konig, sp., nat. size. 1 a. Leaf-scar en- 

 larged and showing the three cicatricules. Loc. Shale over Whistler Seam, 

 Bonnington Pit, Kilmarnock ; communicated by the Rev. David Lands- 

 borough. Jlor. Lower Coal-measures. 



Fiys. 2-4. Bothrodendron WiiJcianum, Kidston, n. sp. 2. Loc. Little 



^ Traite d. paleont. veget., vol. ii., p. 71, pi. Ixi., fig. 9. 



2^. c, p. 13. 



^ Quart. Journ. Geol. Soc, vol. xxviii., p. 169, pi. iv. 



