LINXEAX SOCIETY OF LOXDOX. 63 



other supplied ci'itical and expert anatomical experience based 

 upon tlie study of living plants. The result is a series of beauti- 

 fully illustrated Memoirs published by the Koyal Society of 

 Edinburgh ("On the Fossil Osmundacese," Trans. Roy. Soc. 

 Edin. 1907, 1908, 1909, 1910, 1914). The fossil material was of 

 world-wide origin, but chiefly from New Zealand, and from Russia. 

 In a sequence of plants, dating from the Permian Period to the 

 present day, and shown to be really related to one another by 

 many structural similarities, an anatomical progression was traced 

 which follows most convincingly the successive stratigraphical 

 horizons. It illustrates steps in the medullation of the stele, and 

 in the ampliticatiou of the leaf-trace, and it throws light upon the 

 probable origin of the leaf-gap. Some still hesitate in full 

 acce])tance of the far-reaching conclusions which were drawn; 

 but in most quarters the Memoirs of this magnificent series are 

 held as botanical classics ; and none can be blind to the validity 

 of the methods, or the acuteness of the internal criticism whicli 

 thev show. Though the details of the progression from the 

 protostele to the confirmed soleuostele are not fully demonstrated 

 ill them, the foundations are securely laid, and others are already 

 building upon them. 



In relation to this work on the Eossil OsmundacesB there was 

 also published a short but important joint note "On the origin 

 of the adaxially-curved leaf-trace in the Filicales " (Proc. Roy. 

 8oc. Edin. 1908, p. 433). There are also two later p;ipers by 

 Gwynne-Vauglian alone. The first of these, entitled "Some 

 remarks on the Anatomy of the Osniundaceae " (Ann. of Bot. 

 July 1911), dealt with the structure of the young plant, and the 

 origin of the medullation, and of the foliar gaps in the individual 

 life. The second was his last completed work, and it described 

 a case of " mixed pith " found by Mrs. Gwyune-Vaughan in an 

 anomalous specimen of Osmunda reijuUs. The structure seen in 

 it was held to support the theory that the pith of the Osmundacese 

 is phylogenetically stelar, and not cortical. 



The two series of Memoirs above mentioned embody the most 

 effective work of Gwynue-Yaughiin. But they by no means 

 exhaust it. He originated a most ingenious theory of the stele 

 o( Equisetum (Ann. of Bot. 1901): he discovered the axillary 

 buds of Hehninthostachys (Ann. of Bot. 1902) : he worked through 

 the anatomy of Archangiopteris (Ann. of Bot. 1905). He also 

 wrote on the curious lattice-work structure of certain Fern stems 

 (Ann. of Bot. 1905), and on the minute structure of the tracheae 

 of Ferns (Ann. of Bot. 1908). In all of these liis originality was 

 patent, though restrained. He had also entered upon other work 

 in co-operation with Dr. Kidston. A memoir on Tempslciia was 

 published in Russia (Verb. d. Russ. Kaiserl. Mineral. Gesellschaft, 

 Bd. xlviii. 1911), and a new series " On the Carboniferous Flora 

 of Berwickshire" had been opened with its "Parti, ^tenomijelon" 

 (Trans. Roy. Soc. Edin. 1912). But here the curtain falls 

 prematurely upon a life of investigation full of promise, as in the 



