Bd. XC11. No. 8. XXIV. Jahrgang. 



Botanisches Gentralblatt 



Referirendes Organ 



der 



Association internationale des Botanistes 



für das Gesammtgebiet der Botanik. 



Herausgegeben unter der Leitung 

 des Präsidenten : des Vice- Präsidenten : und des Secretcrs : 



Prof. Dr. K. Goebei. Prof. Dr. F. 0. Bower. Dr. J. P. Lotsy. 



von zahlreichen Specialredacteuren in den verschiedenen Ländern. 



Dr. J. P. Lotsy, 



Chefredacteur. 



No. 8. 



Abonnement für das halbe Jahr 14 Mark 1QA3 



durch alle Buchhandlungen und Postanstalten. 



Alle für die Redaction bestimmten Sendungen sind zu richten an Herrn 

 Dr. J. P. LOTSY, Chefredacteur, Leiden (Holland), Oude Rijn 33 a. 



Referate. 



BAKER, R. T. and SMITH, H. G., A Research on the 

 Eucalypts, especially in regard to their Essential 

 Oils. (Technical Education Series, No. 13. Technological 

 Museum, New South Wales. Sydney 1902. 295 pp.) 



A brief preliminary discussion of the genus is followed by 

 a section on the System of Classification adopted (p. 3 — (>j. 

 Species were not founded on morphological characters alone, 

 but the barks, timbers and oils were also taken into consideration; 

 it was found that such a species was „practically constant in 

 specific characters, however great the ränge of distribution". 

 The Classification of the species on such a broad basis does 

 not favour their union, so that many, that have been synonymised 

 in the past are restored to specific rank in this paper. 



The next section (p. 7 — 14) is devoted to a discussion on 

 the comparative constancy of specific characters of Eucalyptus 

 species. Bentham's antheral system is shown not to be 

 sufficiently natural. — A further section (p. 16 — 20) deals with 

 the „Probable Evolution of the Eucalypts". Angophora is 

 found to be more closely connected with Eucalyptus than the 

 allied genus Tristania. 1t is shown that the leaves of species 

 of Angophora (e. g. A. lanceolata Cav.), whose venation 

 corresponds to that of certain Eucalypts (e. g. E. corymbosa. 

 E. trachyphloia etc.) are provided with an oil, which contains 

 identical constituents to those obtained from the species of 



Botan. Centralbl. Bd. XCH 1903. 11 



