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II. On some Indian Jurassic Gymnosperms. By Nellie Banchoft, B.Sc.{Lond.)y 



F.l/.S., 1851 Besearch Scliolar, Newnham College^ Cambridge, 



(Plates 7-9.) 



Eead 2l8t November, 1912. 



I. Inteoductio:n". 



JLHE fossil plants under consideration are contained in four siliceous blocks sent by 

 Mr. Hayden, Director of the Geological Survey of India, at the request of Professor 

 Seward *. The strata from which the blocks were obtained belong to the Rajmahal 

 Series, a division of the Upper Gondwana Group, and are probably of approximately 

 the same age as the Lower Jurassic (Liassic) rocks of Europe (4, 18, 15). The Eajmahal 

 Series of strata is best developed in Bengal, north of Calcutta, and takes its name from 

 the Eajmahal Hills, where it was first recognised. It also occurs in the Southern Godavri 

 district and in the south and south-west of Madras, The fossil plants now to be described 

 came from the Rajmahal Hills, the exact locality being Amrapara, on the Bansloi 

 River, Puchwara Pass. The geology of the district has been described by Oldham and 

 Morris (19); more fully, with an accompanying map, by Ball (i); by Medlicott 



and Blanford (15); and by R. D. Oldham (18). 



The blocks (referred to in the sequel as I., II., III., IV.) are closely packed with 

 cycadean fronds ; they contain also cycadean stem-fragments, a fructification, a probable 

 fructification-axis, and numerous coniferous branches. Similar Jurassic plants have 

 been figured and described by Messrs. Oldham and Morris and by Dr. Peistmantel in 

 the Memoirs of the Geological Survey of India. Indeed, several of the outstanding 

 features of the four blocks have been already noted by these writers. 



Oldham and Morris ( 1 9) figure the frond on the under surface of block I. (cf. their 

 pi. 21. fig. 3 with PL 9. fig. 3 a) ; also the stem-structures on blocks I. and II. (cf. their 

 pi. 34. figs. 2 & 3 with PL 9. figs. 4 & 1). The impression on block IV. (PL 7. fig. 1) 

 is similar to that shown by Oldham and Morris, pi. 34. fig. 1. Eeistmantel (7, p. 78) 

 describes the block II. stem, noting the similarity to Carruthers's figures of Bucklandla 

 Milleriana and some species of Yatesia, which show alternating zones of large and small 

 leaf-scars. He cannot decide, however, whether this character is accidental or constant 

 in the Rajmahal stems, which, he points out, have generally only the larger scars and 

 are somewhat like those drawn by Williamson (40, pi. 53. fig. 5). The same author (6, 

 Taf. 3, fig. 1 a & b) gives figures of the stem and fructification contained in block II. 

 (PL 9. fif'. 1 ; PL 7. fi^. 2). He refers the stem to Williamsonia^ and considers the 



take this oDDortunity of thanking my friend ITr. Hayden for his ready response to my request for 



* [I take this opportunity of thanking my friend 

 permission to borrow the specimens, and to have sections cut from the blocks.— A. C. Sewakd,] 



SECOND SEKIES. — BOTANY, VOL. VIII. 



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