﻿lii 



PBOCEEDINGS OF THE GEOLOGICAL SOCIETY. [vol. lxxii, 



discovery of new forms of Fern-like fructifications. Zeiller was 

 the first to recognize the generic identity of the Indian genus 

 Trizygia and the European Spheno'phyllv/m ; and his ingenious 

 explanation of the peculiar features of the widespread Indian 

 and Southern-Hemisphei'e genus Vertebraria is the best that 

 has so far been suggested. One of the outstanding features of 

 Zeiller's work is the high standard of excellence of his descrip- 

 tions of plants preserved as impressions : the comparatively few 

 papers on petrified plants show that he was also thoroughly 

 competent as an anatomist, but it is the high standard of his 

 descriptive work, the determination to exhaust eveiy method of 

 attack, and his sanity of judgment and breadth of view that 

 give a permanent value to his achievements. Zeiller's accurate 

 stratigraphical knowledge of the French coalfields enabled him 

 to contribute in no small degree to the better appreciation of the 

 value of plants as indices of geological age. He considerably 

 extended our knowledge of the Glossopteris flora in Brazil and 

 South Africa, and described some new forms from the Lower 

 Grondwana rocks of India ; his paper on ' Les Provinces Botaniques 

 a la Fin des Temps Primaires,' in the ' Revue Generale des Sciences ' 

 (1897), is a model of clear exposition and a highly-suggestive 

 presentation of one of the most fascinating problems of geo- 

 graphical distribution and plant-migration. Another contribution 

 of especial interest from the same point of view is his critical 

 examination of the Siberian plants referred by Schmalhausen to 

 a Jurassic age, which led to their recognition as members of a 

 Permian flora closely allied to those of Gondwanaland. Among 

 many publications dealing with Mesozoic floras, the monograph of 

 the Tongking Bha?tic plants deserves special mention ; it is one 

 of the best works of the kind that we possess, not merely because of 

 its excellent illustrations, but for the wealth of information which it 

 contains and the masterly treatment of the rich material. Zeiller 

 described collections of fossil plants from many parts of the world, 

 from New Caledonia, Madagascar, China, Peru, North Africa, 

 the Balkans, and elsewhere; his 'Elements de Paleobotanique,' 

 published in 1900, though of necessity greatly condensed, is a 

 useful book for beginners as well as for experienced students. 

 For several years Zeiller supplied comprehensive and critical 

 summaries of recent palaeobotanical literature to the ' Bevue 

 Generale de Botanique,' and the thoroughness with which the 

 laborious task was performed is characteristic of the man ; he 



