Mr. Brown on an undescrihed Fossil Fruit. 473 



Since the abstract of my paper was printed in the Proceedings of the So- 

 ciety, the second volume of the Memoirs of the Geological Survey of Great 

 Britain has appeared, which contains an article entitled " Remarks on the 

 Structure and Affinities of some Lepidostrobi." The principal object of Dr. 

 Hooker, the author of this valuable essay, is from a careful examination of a 

 number of specimens, all more or less incomplete, or in various degrees of 

 decomposition and consequent displacement or absolute abstraction of parts, to 

 ascertain the complete structure or common type of the genus Lepidostrobus ; 

 but the type so deduced is in every essential point manifestly exhibited, and 

 in a much more satisfactory manner, by the single specimen of Triplosporite. 

 This does not lessen the value of Dr. Hooker's discovery and investigation, 

 but it gives rise to the question whether Triplosporite, which he has not 

 at all referred to, and therefore probably considered as not belonging to 

 Lepidostrobus, be really distinct from that genus ; and although there are still 

 several points of difference remaining, namely, the form of the strobilus ia' 

 Triplosporite, confirmed by a second specimen presently to be noticed, and 

 in Lepidostrobus the more limited insertion of sporangium, and the very 

 remarkable difference in the form of the unripe spores, hardly reconcilable 

 with a similar origin to that described in Triplosporite, I am upon the 

 whole inclined to reduce my fossil to Lepidostrobus until we are, from still 

 more complete specimens of that genus, better able to judge of the value of 

 these differences. The name Triplosporites however is already adopted, and a 

 correct generic character given, in the second edition of Professor Unger's 

 'Genera et Species Plantarum Fossilium,' p. 270, published in 1850, who at 

 the date of his preface in 1849 was not aware of Dr. Hooker's essay on Lepi- 

 dostrobus, the character of which he has adopted entirely from M. Brongniart's 

 account. 



In October 1849 M. Brongniart showed me a fossil so closely resembhng 

 the Triplosporite, both in form and size, that at first sight I concluded 

 it was the lower half of the same strobilus. On examination however 

 it proved to be of somewhat greater diameter. It was nearly in the same 

 mineral state, except that the crystallizations consequent on loss of substance 

 were rather less numerous ; it diflfered also in the central part of the axis being 

 still more complete ; in the bracteae being more distant and of a slightly 



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