( 213 ) 



IX. — On the Fossil Osmundacese. By R. Kidston, F.R.S. L. & E., F.G.S., 

 Foreign Mem. K. Mineral. Gesell. zu St Petersburg ; and D. T. Gwynne- 

 Vaughan, M.A., F.L.S., Lecturer in Botany, Birkbeck College, London. 

 (Plates I. -IV.) 



(MS. received January 6, 1908. Read same date. Issued separately March 27, 1908.) 



PART II* 



Zalesskya gracilis, Eichwald, sp., and Zalesskya diploxylon, Kidston 



and Gwynne-Vaughan, n.sp. 



While the first part of this paper was in course of preparation a search was made 

 through various palseobotanical publications in the hope of meeting with records of 

 Osmundaceous fossils that had hitherto escaped recognition as such. In so doing our 

 attention was at once attracted by the descriptions and figures given by Eichwald in 

 his Lethwa Rossica of some very fine fossils which were held by him to represent 

 the stems of arborescent ferns. Those in which we were particularly interested were 

 Chelepteris gracilis, Eichwald,! Sphallopteris Schlechtendalii, Eichwald,| Bathypteris 

 rhomboidea, Eichwald,§ sp., and Anomorrhaa Fischeri, Eichwald.|| The figures and 

 descriptions of these plants were quite inadequate for the determination of their true 

 affinities ; but it must be remembered that at the time when these descriptions were 

 written by Eichwald many structural characters which are now regarded as of 

 paramount importance in determining affinities were not recognised as such, even by 

 botanists. To enable us if possible to clear up these difficulties, we wrote to Mons. 

 Michel Zalessky, geologist on the staff of the Comite geologique, St Petersburg, 

 asking if the types of these specimens were known to be in existence, and if any 

 preparations had been made from them suitable for microscopical examination. 



On receiving our letter Mons. M. Zalessky instituted a most laborious search in 

 several museums, and was eventually successful in finding the types of the four genera 

 already mentioned in the Museum of the Institute of Mines, St Petersburg. No 

 sections for microscopical examination had ever been prepared from any of the stems, 

 though the microscopical structure of the petiole base of Sphallopteris Schlechtendalii 

 had been imperfectly described by Eichwald,H and that of Bathypteris rhomboidalis 

 by Schmalhausen. ## 



* Part I., Trans. Roy. Hoc. Edin., vol. xlv., part iii. (No. 27), pp. 759-780, pis. i.-vi., 1907. 



t Letheea Rossica, vol. i., p. 98, pi. iii., figs. 4, 5, and 6, 1860. 



| Ibid., vol. L, p. 93, pi. iii. figs. 1-2, pi. xx. figs. 2-5. 



§ Ibid., vol. i., p. 96, pi. iv. figs. 1-2 ( = Tubicaulis rhomboidalis, Kutorga (pars), Verhandl. d. Miner. Gesell. zu 

 St Petersburg, pi. i. fig. 6, 1844). 



|| Ibid., vol. i., p. 102, pi. iv. figs. 3-4. 



IT Ibid., pi. xx. figs. 2-5. 



** " Die Pflanzenreste d. Artinskischen und Permisehen Ablagerungen," etc., Mem. du Comite' ge'ol. (St Petersburg), 

 vol. ii., No. 4, pp. 9 and 36, pi. iii. figs. 6-7, 1887. 



TRANS. ROY. SOC. EDIN, VOL. XLVI. PART II. (NO. 9). 32 



