52 PEOCEEDIIS'GS OF THE 



of the fact, long overlooked, that Griffith had already described 

 and figured this organ, more than 20 years before. Eenault 

 had an important share in the preparation of the splendid 

 volume on Silieified Seeds, published posthumously in Brongniart's 

 name. 



It was only for a short time that Eenault delivered regular 

 courses of lectures on Fossil Botany, but his teaching work bore 

 permanent fruit in the publication of his famous ' Cours de 

 Botanique Fossile,' in four volumes, 1881-85, by far the most 

 important general work on the subject up to that time, and still 

 an invaluable storehouse of facts, based almost wholly on original 

 observation. 



A somewhat earlier and more special work, tlie ' Structure 

 comparee de quelques Tiges de la Flore Carbonifere," 1879, had 

 prepared the way ; for in this memoir, among many other researches 

 of importance, he published his complete account of all the organs 

 of the extinct Gymnospermous family Cordaiteae — perhaps the 

 greatest contribution which he, or any botanist before him, had 

 made to our knowledge of the plants of the past. It may be 

 mentioned that Eenault, in observing the structure of the pollen- 

 grains within the pollen-chamber of Cordaiteau and other fossil 

 seeds, was led to anticipate the discovery o£ Ikeno and Hirase, 

 suggesting the probability that in plants of this group fertilization 

 took place by means of sperraatozoids. 



Eenault's work on the higher plants of the Palaeozoic Period 

 was crowned by the completion, in 1896, of the magnificent 

 ' Flore Fossile d'Autun et d'Epinac,' of which the first volume is 

 the work of Zeiller, and the second tliat of Eenault. This was in 

 many respects his finest work, and the series of more than 

 60 plates, by which the volume is illustrated, is a worthy monu- 

 ment of the mass of detailed research which the text contains. 



Eenault was much engaged in controversy, more especially with 

 our own distinguished countryman, Williamson. They differed 

 principally on the question of the affinities of the Sigillariese and 

 Calamodendreje ; families which Williamson regarded as essentially 

 Cryptogamic, belonging to the Lycopodinean and Equisetineau 

 series respectively, while Eenault, following Brongniart, was led 

 to place them among Gymnospermous Phanerogams, relying, to a 

 great extent on the fact that these plants developed secondary 

 wood, like Phanerogamic trees. The result has justified the 

 opinion of Williamson rather than that of his great French rival ; 

 but it has been well pointed out, that even if wrong in detail, 

 Eenault and the French school represented by him deserve great 

 credit for having realized that among related plants, some might 

 be on one side, some on the other, of the ideal Phanerogamic- 

 Cryptogamic boundary. Eecent work on other groups has abuu- 

 dantly justified Eenault's point of view. 



During the last ten years of his life Eenault allowed himself to 

 be to a great extent diverted from the important stiidits on which 



