4 Notes and Comments. 



those of the workers of to-day ; and the spirit in which those 

 early students approached them might well be emulated to-day. 

 And even at that early period the spirit of evolution was in the 

 air, and even to-day wor,kers find themselves in complete 

 sympathy with the palaeontological studies that were being^ 

 carried on at the time when the ' Beagle ' had scarcely started 

 on her momentous voyage. The following translation of a 

 passage from the Introduction to Brongniart's ' Histoire de 

 Vegetaux Fossiles,' which was published in 1828, and is quoted 

 by Dr. Scott, might almost have been written yesterday. 



THE STRUCTURE OF FOSSIL PLANTS. 



' Everyone will readily admit that anatomical characters,, 

 those which relate to the intimate organisation of the plant, 

 have more value than the external forms ; it is to these charac- 

 ters, then, that we ought to attach the most importance when 

 one is able to observe them, and when one cannot do so, one 

 should seek to discover in the external form of organs, such 

 modifications as may, so to speak, be the expression of the 

 internal character, and may enable us to form an estimate 

 of its modification. The nutritive vessels, forming the frame- 

 work which determines the relations of position and often even 

 the form of organs, are evidently more important than the 

 parenchyma which surrounds them, and which may mark 

 the most essential characters of an organ. The mode of dis- 

 tribution of the vessels alone may put us on the track of the 

 true affinities of plants. Their arrangement is consequently 

 the principal thing to observe in each organ.' 



LEAVES OF CALAMITES. 



From Mr. H. Hamshaw Thomas we have received a paper 

 ' On the Leaves of Calamites ' (Calamocladus Section), reprinted 

 from the ' Philosophical Transactions of the Royal Society of 

 London,' a publication which has contained so many of the 

 classical papers on Palaeo-botany. Mr. Thomas's memoir is 

 largely based on the work he has done with the microscope on 

 material discovered from the Halifax Hard Bed — a bed which 

 from the fact that its contained fossils retain their structural 

 details, has proved a veritable mine of material for the worker 

 in Fossil Botany. In an elaborate and detailed manner Mr. 

 Thomas throws some Hght upon the question of the primitive 

 megaphylly or microphylly of the Equisetales, and on their 

 relationship to the other members of the Pteridophyta. The 

 relationship of the Calamites to the Sphenophyllums is further 

 brought out in the structure of the young stems and twigs he 

 describes. The steles of the latter were almost invariably 

 triarch, and the author shews that this was also the case in 

 some Calamites. This paper admirably shews that there is 



Naturalist, 



