277 



Gs-2 and closed with a droplet of paraffin introduced with a heated glassrod. At 28 

 to 30 C. the air in Lr, which space can be relatively small, will soon be free from 

 oxygen and the anaerobes on Ka can begin to grow. To further the absorption of 

 oxygen from the agar Ka in Gs->, Oidium may also be added to it, but then a thin 

 layer of malt agar without Oidium should be poured on the surface of Ka to obtain 

 a germ-free surface for the sowing of the anaerobes. Oidium being strictly aerobic 

 the mycelia do not perceptibly grow through this protecting layer. 



If the glass dishes have good dimensions and the space Lr is not too small, one 

 can sideways look through the glass wall and follow the development of the anaerobic 

 colonies on Ak. So it is easy to decide when the moment for further observation has 

 come without it being necessary to remove plate Ka from the Oidium plate Op. and 

 thus prevent too early opening. 



When it is time to open, liquefied malt agar must be at hand to be poured out over 

 the Oidium plate, especially in the groove formed by Gs- 2 , as soon as plate Ka is to 

 be restored to its place. The fresh food causes new oxygen absorption by Oidiuin 

 and the growth of the anaerobes can go on. 



For the success of the experiment it is essential to mind the following. The pla- 

 cing in the incubator should be managed in such a way that the Oidium layer Op 

 comes in the cooler, and the cover Gd as also plate Ka in the warmer part. The vapour 

 in Lr will then condense in Op and not on the surface ofA'o. In the reserved position 

 Ka will become moist, the colonies intermingle and the experiment fails. Hence the 

 figure is represented in such a position that the colder air is above, the warmer below, 

 a.b is the actual state in an incubator with bottom-heat. How simple all this may 

 appear, in the execution it will be found necessary to pay special attention to it. 



In this way it is possible from the ordinary crude butyric-acid fermentations, 

 obtained as described above, to separate three distinctly different Amylobacter species, 

 two of which I described already before (Proceedings Vol. 12, Pag. 973, 1903) under 

 the names A. (Granulobacter) saccharobutyricum and A. (G.) pectinovorum, while 

 from the butyl-alcoholic fermentations two species were isolated, one of which pro- 

 duces large slimy colonies and was described as A. (Gr.) biitylicum (Archives Neer- 

 landaises, ire Serie, T. 29, Pag. 2), whereas the other, which secretes no slime, has 

 not yet been investigated. The colonies of all these species colour dark blue with iodine 

 like starch, the staves and clostridia containing a great quantity of granulose. 



The butyric-acid and butyl-alcoholic fermentations acquired in other ways than 

 the above mentioned have not yet been examined thoroughly. 



As the anaerobic Sarcina ventriculi likewise develops very well on malt-infusion 

 agar at 30 tot 37 C. (Proceedings 28 April 1911, Pag. 1412), this species may be 

 isolated just in the same way as the above. 



As regards the spore-producing bacteria of the real protein putrefaction the 

 Oidium-p}ate. may be prepared just as in the experiment described, only for the culti- 

 vation of the anaerobes themselves in Gs? it is better to make use of broth agar with 

 0.5 or i % common salt, either with addition of 2% glucose or not. In this case, too, 

 nutrition with carbohydrates gives in some species rise to production of granulose, in 

 others not. 



Another anaerobe isolated by the Oidium-method is Bacillus acidi urici (Procee- 

 dings 23 April 1909, Pag. 990), which ferments uric acid to carbonic, ammonium 



