544 Chemisches, Pharmaceutisches. — Necrologie. 



E. corymhosa by ether was equal to O'84'^/o, of which 0'0224"/o was 

 wax. From the fresh young leaves of E. cinerea the total removed 

 was P/ü of which O'SöS'^/o was wax. The elastic substance was found 

 to be a very good form of Caoutchouc, thus bringing the Myrtaceae 

 into those families of plants yielding this substance, and showing 

 that both Eucalyptus and Angophora are "India-rubber" bearing 

 plants. The best solvent was found to be Chloroform as the other 

 usual solvents acted but little upon it. The sheet rubber obtained 

 by the evaporation of the Chloroform had great elasticity. did not 

 melt below 250° C, and quickly regained its elasticity on cooling. 

 In every other respect it acted as did crude commercial "rubber." 

 The rubber was also obtained from the plant by destroying the leaf 

 substance by allowing the material to remain for five days in a 5'^/o 

 Solution of potash, and removing the "rubber" by mechanical means. 

 When heated in melted sulphur it vulcanised very well. If Euca- 

 lyptus "rubber" was obtained in quantit}'' it would have considerable 

 commercial value. This, howevcr, from the natural plant is not pos- 

 sible, as the collection would be too costl}^, without considering the 

 rapid alteration it undergoes on the leaf. Whether it would be pos- 

 sible to polymerise some of the terpenes of the Eucalypts is a ques- 

 tion worthy of consideration. The amount soluble in Chloroform in 

 five days was lO-ö'^/o of the larger amount extracted by mechanical 

 means. From 500 grams of buds and young leaves, when placed in 

 Chloroform for five days after complete extraction with ether, 785 

 gram of rubber was obtained. The close affinity existing between 

 the Angophoras and the "Bloodwood" group of Eucal3^pts in every 

 respect except the operculum in the bud stage was again referred 

 to. The author would like to reserve to himself the chemical investi- 

 gation of the white powdery substance and also of the vegetable wax. 



Author's notice, 



Fischer, E., Gustav Otth, ein bernischer Pilzforscher 

 1806—1874. (Mitteilungen der Naturforschenden Gesellschaft in 

 Bern 1908. 32 pp. 8"^. mit Bildniss.) 



Kurze Biographie und Würdigung der wissenschaftlichen Ar- 

 beiten von Gustav Otth, der ursprünglich Militär, sich später in 

 sehr fruchtbarer Weise mit der Pilzkunde beschäftigt hat. Es hat der- 

 selbe namentlich in mehreren Nachträgen zum Verzeichnisse schwei- 

 zerischer Schwämme von Frog eine ganze Reihe von Pilzen, bes. 

 Uredineen, Hymenomyceten und Ascomyceten neu beschrieben. Von 

 ihm sind auch die Gattungen Mitschkia und Pucciniastruni aufgestellt 

 worden. Die meisten seiner sehr sorgfälti.^en Untersuchungen und 

 Beschreibungen sind ziemlich unbeachtet geblieben, bis sie dann 

 von Jaczewski wieder ans Tageslicht gezogen wurden. Auch die 

 vorliegende Biographie soll dazu dienen, das Andenken an diesen 

 Mann, dessen Name sich würdig an denjenigen des bernischen 

 Lichenologen Schaerer und des Mykologen Frog anreiht, lebendig 

 zu erhalten. Ed. Fischer. 



Aussegeben: 17 November 1908. 



Verlag von Gustav Fischer in Jena. 

 Buchdruckerei A. W. Sijthoff in Leiden. 



