ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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modification of J. af Klercker’s arrangement consists in substituting for 
the caoutchouc ring a quickly setting cement with which to fasten on the 
cover-glass, fig. 29. The disadvantage of the caoutchouc ring was 
that it prevented the observation of the whole cultivation space, and 
necessitated the use of a second object-holder, the effect of which was to 
raise the preparation so far above the stage that the use of the diaphragms 
was injuriously affected. 
By the author’s simplification in the mode of fixing the cover-glass 
it is possible to observe the whole of the cultivation space and to dispense 
with the second object-holder. 
Apparatus for Cultivating Anaerobic Bacteria.* — The apparatus 
devised by Prof. F. G. Novy consists of a cylindrical glass vessel closed 
by a hollow glass stopper, at opposite sides of which are two apertures 
(fig. 30). From one of these openings a glass tube runs nearly to the 
Fig. 30. 
bottom of the flask. From the neck of the flask project at right angles 
two glass tubes which can be closed by means of stopcocks. The openings 
of these tubes in the neck of the flask are made to correspond with the 
openings in the stopper. It is, of course, obvious that if a half turn be 
given to the stopper the flask will be closed. 
The apparatus can be used for anaerobic cultivation either by filling 
it with some gas or by exhausting the air. The apparatus is used by 
first putting the inoculated tubes inside the flask. The stopper is then 
* Centralbl. f. Bakteriol. u. Parasitenk., xiv. (1893) pp. 591-5 (2 figs.). 
