THE CARBONIFEROUS ROCKS OF CANONBIE, DUMFRIESSHIRE, ETC. 767 



little distance below the more elongated leaf scar, which does not occupy the whole 

 width of the rib and which is surmounted by a distinct lunate scar. These characters 

 at once distinguish the two species. Sigillaria polyploca appears to be restricted in 

 its distribution to the Middle Coal Measures. 



Sigillaria Canobiana is also easily known from Sigillaria Youngiana, Kidston,* 

 which has much more contracted and expanded ribs, their width about midway between 

 the leaf scars being only half the width of the rib shortly below the leaf scar, by the 

 form and position of the leaf scar which is placed about the centre of the inflation, and 

 by the delicate very short lines, mostly upright, with which the surface of the inter- 

 foliar cortex is ornamented. 



Sigillaria Youngiana, which comes from the Possil Ironstone group of the Carbon- 

 iferous Limestone series, and Sigillaria Canobiana are the only two ribbed Sigillaria 

 yet discovered in the Lower Carboniferous Rocks of Britain, and the first mentioned is 

 only known from a single specimen. 



Localities A and B. 



Stigmaria, Brongniart, 



Stigmaria flcoides, Sternb., sp. 



Stigmaria flcoides, Sternb., sp. (See ante, p. 7 57.) 

 Locality B. — Common. 



Stigmaria flcoides, Sternb., sp. var. 

 Locality B. 



Stigmaria (? Stigmariopsis) rimosiformis, Kidston, n.sp. 



(Plate Ii. fig. 15.) 



Description. — Rootlet scars in structure and position as in Stigmaria jicoides; 

 cortex ornamented with irregularly flexuous lines, which converge towards the rootlet 

 scars, especially on the two sides facing the axis of the rhizome. 



Remarks. — This Stigmaria has some similarity to the Stigmaria jicoides, var. 

 rimosa, Goldenberg,f but in Stigmo.ria rimosiformis the ridges are more numerous, 

 finer, and converge towards the scars, where they are thinner and closer than on the 

 inter- rootlet portion of the cortex, whereas in Stigmaria jicoides, var. rimosa, Golden- 

 berg, the ridges are coarser and more distant, and have the tendency to bend round 

 the scars, not converging towards them. 



It seems to me possible that both Stigmaria Jicoides, var. rimosa, Gold., and 



* Sigillaria Youngiana, Kidston, Proc. Roy. Phys. Soc. Edin., vol. xii. p. 261, pi. vi. figs. 2, 2a. 

 t Stigmaria Anabathra, var. rim,osa, Goldenberg, Flora Sarssp. foss., Heft iii. p. 19, pi. xiii. fig. 16. 

 X See Kidston, Carboniferous Lycopods and Sphenophylls, — Trans. Nat. Hist. Soc. Glasgow, vol. vi. (new series) p. 

 108, 1001. 



