SCIENCEthus to one whose investigations have been confined to those species growing in the temperate zones, Cinchona furnishes splendid opportunity for the extension of his work to such allied tropical species.A tropical rain-forest presents peculiar conditions. The plants do not show the marked periodicity characteristic of colder and dryer regions. Where the temperature and rainfall are so nearly constant a t all times of the year ss at Cinchona, one is likely to find all of the stages in the life history of a species on almost any single day, and conditions are favorable for collecting the year around. I n the plants of a tropical rain-forest, moreover, there is much less cutin, fewer hairs, etc., to interfere with the penetration of fixing solutions, and hence there is the probability of better fixation. That such is not in all cases true is evidenced through the impermeability of the walls of fern sporangia, and the hairiness of the leaves of the Gymnogrammeae may be as striking here as elsewhere.To the cytological collector a compound microscope is an absolute necessity; and such a permanent station as that at Cinchona, therefore, seems to be the only solution to the accessibility of such regions. The buildings at Cinchona, including two cottages, a two-room laboratory, the drying house, the dark room, the greenhouses and the garden, were all in good condition when I left there in December last. Through the kind offices of Mr. William Harris at Hope Gardens servants were made available, and one's personal needs adequately supplied. The space is s&cient for a number of investiigators at one time, and life there is very pleasant indeed.
Coblents u. Nay: Ferrum Reducturn. wollc nur unbedeutend. Die Anderung wird beeinfluibt durch die Substanzen, welche aus der Baumwolle bei der Mercerisabion entfernt werden. Diescs Ergcbnis scheint die Untersuchungcn von H. 0 s t und I?. W e s t h o f (Chcm.-Ztg. 1909, 199) zu bestatigen, daB mcrcerisierte Cellulose in ihrer chemischen Zusammensetzung nicht von der ursprunglichcn Cellulose verschieden ist. Andererseits laBt die hiiherc Loslichkeit der aus merccrisierter Baumwolle licrgestellten Nitrocellulose darauf schliciben, daB eine Anderung im Molekul der Ccllulose vor sich gegangen ist. 3. Die Loslichkeit dcr Nitroccllulose in Atheralkohol ist nicht nur vom Wassergehalt und der Zusammensetzung der Mischsaure, sondcrn auch von der Art der Vorbereitung der Baumwolle abhgngig. Sic stcigt bci der Verwendung von merccrisierter Baumwolle und wird noch groiber bei Benutzung von stark geblcichter Baumwolle. Mcrccrisierte Baumwolle hat auf die Liislichkeit der Nitrocellulose in absolutem Alkohol kcinen EhfluB, dagegcn wird die Loslichkeit in absolutem Alkohol bei Vcrwendung stark gebleichter Baumwolle groBer. 4. Langere Zeit im Kohlcnsaurestrom auf 150" erhitzte Baumwolle andcrt sich in ihrer Zusammcnsetzung nur wenig. Aucli die daraus hergestellte Nitrocellulose hat, nahezu dic glciche Zusammcnsetzung wic Nitrocellulosc, welche aus normal vorbereiteter Baumwolle unter den glcichen Bedingungen erhalten wurdc.
forms may be mentioned the following: It can easily be cleaned. The platinum spiral extending the full length of the tube insures complete combustion.This spiral can readily be removed for repairs in case of injury. The apparatus is convenient to handle and owing to its tall form connects with a Hempel pipette without the use of a stand.
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