﻿1 6 INTRODUCTORY. 



found. With the work of Williamson and Carruthers the exact investigation of the 

 Cycadeoidese may be said to have been fairly begun. 



Since the time of Carruthers various details have been added to our knowledge 

 of the trunk structure and ovulate fructification of the Isle of Wight genus Ben- 

 nettites. In particular, Solms-Laubach, in his restudy of the type material, gave a 

 much clearer account of the structure of the ovulate strobilus, and discovered its 

 dicotyledonous embryos (156, 157). 



Much additional interest has also been lent to the Isle of Portland as a cycad 

 locality by the discovery, about 1895, of Cycadeoidea gigantea described by Seward 

 (144). This fine silicified trunk is one of the largest and tallest complete speci- 

 mens known, its height being 1.18 meters and greatest diameter 41 cm. It is now 

 on exhibition in the fossil plant gallery of the British Museum. 



OTHER EUROPEAN CYCAD LOCALITIES. 



In addition to the European localities already mentioned there are few others 

 requiring mention in any other than a wholly complete list. Various trunks have 

 been reported from Germany, also Belgium, Poland, and Russia. Eichwald, as early 

 as i860, figured several supposed cycadean and other trunks from the cupriferous 

 sandstones of the Carboniferous terrane of the Altai in the department of Orenburg 

 (44, plate xvii, fig. 2, etc.), and further material from this region may prove of 

 great interest. 



CYCADS OF INDIA. 



The occurrence in the Gondwana system of various cycadean trunks associated 

 with WilHamsonia fruits and a plenitude of cycadaceous leaves is of the greatest 

 interest as indicating that the dominating feature of the Indian Jurassic was a 

 highly developed cycad flora closely related to and probably contemporaneous with 

 that of Europe and America. The great extent of this Jurassic cycad flora of India 

 was first made known by Oldham & Morris in 1863 (105), although, as these 

 authors state (p. 14), several earlier references to the occurrence of cycads in India 

 had been made. 



In addition to figuring and describing a large number of fronds, Oldham & 

 Morris mention a considerable number of "silicified trunks of cycads," many of 

 which were said to be well preserved, as shown by microscopic examination. This 

 reference, as well as that in their introduction (105, p. 5), to "large quantities of 

 other silicified stems, chiefly exogenous, in the upper group of the Rajmahal series 

 (Bengal) " is, however, rather vague. They also mention a number of smaller 

 trunks from Amrapara, Puchwara Pass, which were associated with Paleozamia 

 {r=Ptilophylhtm) leaves. Some of these are figured and they, as well as the types, 

 are again mentioned with reference to Oldham &: Morris" figures by Feistmantel (48), 

 who suggests very reasonably that they may possibly be related to the Wealden 

 genus Bucklandia. The interesting observation is added that on the same slab 

 with one of the trunks there is an " involucrum " of WilHamsonia gigas. Thus we 



