626 



31E. E. D. VEKXOX OlST THE GEOLOGr AXD [DeC. I912, 



fact that many of the species have never been recorded from these 

 higher horizons. The majority of the species occur both in the 

 Middle Coal Measures and in the Lower Coal Measures of Britain ; 

 but the presence of a number of plants, such as Oligocarpia hron- 

 gniarti, Zeilleria delicatida, and Lo^icJiojyteris hricei, which are 

 restricted to the Middle Coal Measures of Britain, at once differen- 

 tiates the flora from that of the Lower Coal Measures. 



It may perhaps be contended that a thin representative of 

 the Lower Coal Measures might be present in the north of the 

 Warwickshire Coalfield, where the thickness of Productive Coal 

 Measures reaches its maximum. In this connexion the species 

 tabulated below, which are from the two lowest seams — the Bench 

 Coal and the Double Coal — towards the base of the Coal Measures 

 (see vertical section, PI. LXI), are of especial interest. 



DiSTEIBTJTION OP IJPPEE CaEBOXIT'EEOUS SpECIES WHICH OCCUE IX 

 ASSOCIATIOX WITH THE LoWEST COALS IX THE WaEWICKSHIEE COALFIELD. 



Species. 



Middle Coal 

 Measures. 



Lower Coal 

 Measures. 



Equise tales. 



Calamites ramosus Artis 



Calamites varians ^i&cn\) 



X XXXX XX XXX XXXXX 



1 

 ! 



X 

 X 



Ca lamites tindttlatus Sternb 



X 



Annularia radiata Bvongn 



X 



Calamocladus cliarcBformis Steriib 





Splienoplij'llales. 

 Sphenophyllum cuneifolium Sternb. 



X 



Sjph. cuneifolium\2tx. saxifraqisfolium (Sterub.) . 

 Splienopliyllum myriopliyllum Crepiu 



X 

 X 



Pteridospevms and Primofilices. 

 Alethopteris loncMtica (Scblotb.) 



X 



Weuropteris ohliqua ^YOugu 



X 



Lycopodiales. 

 Lepidodendron aculeaticm Sternb 



X 



Lepidodendron lycopodioides Sternb 



X 



Lepidodendron ohovatum Sternb. 



X 







C r d a i t a 1 e s. 

 Cordaianthus pitcairnice (L. & H.) 



X 1 





1 



Prom the presence in the foregoing list of Lejjidophloios laricinus 

 and Calamocladus e7iara/or»n'5, which are unknown from the Lower 

 Coal Measures of Britain, it is concluded that in the Warwick- 

 shire Coalfield the Lower Coal Measures are entirely 

 absent, and that the lowest palaeobotanical horizon is 

 that of the Middle Coal Measures. 



