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E. N. Thomas. 
that the soil conditions present the dominating factors. Thus the 
basaltic plain running N.W. and S.W. is characterised by grass 
steppe with the minimum of trees, while the Silurian area bears a 
Eucalypt forest formation filled in with scrub. The Tertiary sands 
are covered with a maquis of Epacrids, Orchids and Myrtaceous 
plants, while the strand bears the usual halophytic flora. 
In a paper on the Australian Ebenaceae, Mr. Hiern recorded 
his investigations into the taxonomic value of histological characters 
within this order, which has long been associated with his name. 
Dr. E. M. Berridge discussed the Systematic Position of 
Casuarina and its Allies, and showed that its once isolated and 
supposed primitive position has been undermined by the increase 
of knowledge concerning chalazogamy on the one hand, and 
concerning the inflorescence, flower and cupule of Fagaceae on the 
other. She supports Hallier’s original view that the ancestors of 
the Cupuliferae were allied to the Rosaceae. 
The series of Eucalyptus papers mentioned above included:— 
1. “The Species Concept with special reference to Eucalypts,” 
by J. N. Maiden. The author emphasised, with reference to his 
own detailed work on Eucalyptus, the importance of obtaining a 
wide and comprehensive knowledge of a species, which must be 
treated as a whole if it is to yield satisfactory conclusions. Species 
correspond to the evidence of our senses, and as such will never be 
abandoned, although it is obvious that attempts to define our 
conceptions of species lead to illogical and often ridiculous positions. 
2. “ The Correlation between the Specific Characters of the 
Tasmanian and Australian Eucalypts,” by Mr. R. T. Baker and 
Mr. H. S. Smith. The authors review their work on Tasmanian 
Eucalypts in the light of twenty-five years’ experience of the genus 
on the mainland. They see reason to believe that the Tasmanian 
species are the more recent. Notwithstanding the variety of soils, 
climates, altitudes, etc., from which the genus has been examined, 
the authors find that certain very constant botanical and chemical 
features charcterise the whole genus. 
3. “ Notes on the Evolution of the Genus Eucalyptus,” by 
Mr. N. H. Cambage. In this paper the changing characters of the 
genus were reviewed from Eocene times up to the present day. 
They show that the opposite sessile broad-leaved form with 
transverse venation was the earliest, and that the spread into 
colder regions was associated with the development of long narrow 
leaves with parallel venation. This change was accompanied by 
