Yol. 59.] OCCURKENCE OF DJCTYOZAMITES IN ENGLAND. 217 



18. On the Occurrence of Dictyozamites in England, with 



Remarks on European and Eastern Mesozoic Eloras. By 



Albert Charles Seward, Esq., M.A., F.R.S., E.L.S., F.G.S., 



Fellow of Emmanuel College, Cambridge. (Read February 25th, 



1903.) 



[Plate XV.] 



Among several species of Inferior-Oolite plants recently collected by 

 the Rev. John Hawell, M.ii., E.G.S., and sent to me for examination, 

 I found a few fragments of Dictyozamites, a genus of especial interest 

 from the point of view of the geographical distribution of Mesozoic 

 plants. Mr. Hawell obtained the plants from a bed of ironstone on 

 the northern face of the Upleatham outlier, near Marske -by-the-Sea, 

 in Yorkshire ; most of the material was dug out from an old heap 

 of refuse thrown aside during boring operations, but the plant-bed 

 was also investigated in situ} 



The locality is mentioned on the 6-inch Ordnance Survey-maps as 

 Marske Quarry; it is situated 1 mile directly south of Marske, 

 and about 500 feet above sea-level. This plant-bed occurs low down 

 in the Estuarine Series, and is probably of Lower Estuarine age ; 

 but in the neighbourhood of Marske, Mr. Hawell informs me, 

 there is apparently no distinct line of division between the Lower 

 and the Middle Estuarine Series. 2 



The generic name Dictyozamites was proposed by Oldham in 

 1862 3 for some pinnate fronds discovered in strata of laminated 

 clay, converted by igneous agency into a porcellanous rock, at the 

 eastern end of the Puchwara Pass in the Rajmahal Hills. The 

 fragments represented in figs. 5-8 (PI. XV) were drawn from a 

 piece of this rock in the British Museum (Natural History) Collec- 

 tion. 4 Morris, as joint author with Oldham of the first volume of 

 the ' Fossil Flora of India,' referred the specimens to Gutbiers genus 

 Dictyopteris, a term applied to certain Palaeozoic species agreeing in 

 all respects, except in the reticulate venation of the pinnules, with 

 the well-known genus Neuropteris. Presl's generic term Linopteris 5 

 has been substituted by some authors for Dictyopteris. Morris 

 instituted the species Dictyopteris falcata for the Rajmahal plant, 

 describing certain specimens as D. falcata, var. obtusifolia. 6 The 

 name Dictyopteris expressed Morris's view that the leaves were those 



1 Mr. Hawell kindly supplied me with this information, and I am indebted 

 to him for generously allowing me to describe the specimens which form the 

 subject of this communication. 



2 For the geological structure of this part of Yorkshire, see Fox-Strangways 

 (92). [Numerals in parentheses throughout this paper refer to the Bibliography 

 on p. 230.] 



3 Oldham & Morris (63) p. 38. 



4 Specimen No. 52546. 



5 For a figure of Linopteris, see Zeiller (00) p. 108. 

 B Oldham & Morris (03) pi. xxiv, fig. 2. 



Q.J.G.S. No. 234. q 



