Agricultur, Horticultur, etc. — Chemisches, Pharmaceutisches. 543 



deiim distichum nutans und Hordeum erectum die Einreihung in das 

 Atterberg'sche System versucht. Mischgersten, die offensichtlich aus 

 mehreren Formenkreisen bestanden, wurden ausser Acht gelassen. 

 Aber auch Gersten, die als rein betrachtet werden konnten, wiesen 

 immer neben der vorherrschenden Form noch andere auf.? 



Weder bei Bezahnung der Rückennerven, noch bei Ausbildung 

 der Basalborste wurde Einheitlichkeit angetroffen. Verfasser schliesst 

 sich Broili's Ansicht, dass die beiden erwähnten Merkmale keine 

 sicher zu unterscheidenden sind, an. Bei einer Pflanze der schottischen 

 Perlgerste fand er an derselben Pflanze eine Reihe verschiedener 

 Ausbildungen der Basalborste: verkümmerte und verzweigte, unbe- 

 haarte bis dichtbehaarte, langhaarige und tadenwollige. Fruwirth. 



I 



Bouchep, V., Nature des ferments solubles hydratants con- 

 tenus dans les gommes. (Bull, des Sc. pharmacol. 1908. t. XV. 

 p. 304.) 



L'auteur a recherche et trouve de F^mulsine dans les produits 

 gommeux les plus divers: Gommes des Sterculiacees, Bixacees, 

 Rutacees, Legumineuses, Rosacees, Terebinthacees, Combretacees; 

 gommes-resines des Coniferes, Terebinthacees, Guttiferes, Pro- 

 teacees; tano-gommes des Legumineuses et Moringacees; resines: 

 copals, dammar, sandaraque, elemi, shorea. La presence de l'emul- 

 sine parait donc generale dans les produits gommeux. F. Jadin. 



I 



Smith, H. G., On the elastic substance occurring on the 

 shoots and young leaves of Eucalyptus corymbosa and 

 some species of Angophora. (Roy. Soc. N. S. Wales. Abstr. 

 Proc. May 6, 1908. p. VII- VIII.) 



In this paper the author records the results of a chemical 

 investigation of this elastic substance which is formed at the time 

 the shoots are developed. As the buds expand, and the individual 

 leaves are formed, the elastic coating Stretches and expands with 

 them. Changes then rapidly take place as the need of the protective 

 coating is removed, and by light and oxidation a white powdery 

 substance is formed, which remains on the surface of the leaves, 

 and although no white coating can be detected upon the mature 

 dull green leaves of this group of Eucalypts, yet it can readily be 

 removed by ether with only five minutes contact. A small quantity 

 of a vegetable wax is formed at the same time, and this can be 

 removed from the powdery substance .by Solution in boiling petro- 

 leum ether, and purified from boiling alcohol. As the genus Euca- 

 lyptus descends and that group having white pulverulent young 

 growth is reached, including such species as E. cinerea, E. pidve- 

 ridenta , E. glohidus, etc., then it is found that the wax has increased 

 considerably in amount. and that the white appearance of these 

 young leaves is due to the presence of a comparatively large amount 

 of this wax, together with the white substance found on the leaves 

 of the earlier members of the genus. The reason why the leaves of 

 the "Bloodwoods" (to which group E. corymbosa belongs) are not 

 pulverulent, is that there is a deficienc}^ of the wax. In those species 

 where the wax predominates, the elastic substance does not occur, 

 the corresponding protective medium being supplied by the wax. 

 The amount of material removed from the fresh young leaves of 



