ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
545 
water containing anilin, differentiation being effected by alcohol and 
essence of cloves, or picric acid dissolved in absolute alcohol, or Benda’s 
light green. After Perenyi’s liquid or sublimate, he used the following 
method : — Overstain with Delafield’s haematoxylin, decolorise with nitric 
acid of 0*5 per cent, strength, or with very dilute Perenyi’s fluid, wash 
with water, stain with alcoholic eosin. 
For the study of the blood, the following liquid was used : — Acetic 
acid, copper acetate, copper chloride, osmic acid, thionine, 1 grm. 
each ; distilled water, 400 grm. This is added to the blood on a slide, 
and both fixes and stains after about two minutes. 
For the study of the nervous system, he used the following method 
instead of that of Golgi. The preparations were placed for 48 hours 
in the following: — 5 per cent, solution potassium bichromate, 3 parts; 
20 per cent, formol, 1 part ; and then for 24 hours in 1 per cent, nitrate 
of silver solution, both solutions being kept at 40° C. 
Isolation of Nitrification Microbes from the Soil.* — According to 
Herr V. Omelianski, the media suggested by Winogradsky are the most 
suitable substrata for isolating nitrification microbes, silicon jelly for 
nitrite-formers, and nitrite-agar for nitrate-formers. For making silicon 
jelly it is necessary to use soluble water-glass (sp. gr. 1 *05-1*0 6) and 
hydrochloric acid (sp. gr. 1*10). A mixture of equal parts is made and 
dialysed until the chlorine reaction is no longer given with silver nitrate. 
Besides the foregoing, the following solutions are required : — 
Solution i. Potass, phosph. 1 grm. ; ammon. sulph. 3 grm. ; mag. 
sulph. 0*5 grm.; aq. dest. 1000 ccm. 
Solution ii. Ferri sulph. 2 per cent. 
Solution iii. Saturated solution of sodium chloride. 
Solution iv. Magnesia-milk, i.e. a suspension of carbonate of mag- 
nesia. 
To 50 ccm. of the silicic acid solution, 2*5 ccm. of the first and 
1 ccm. of the second solution are added. A loopful of salt is required 
for each plate, and as much magnesia-milk as will impart a milky 
appearance to the jelly. The plates are best inoculated by rubbing a 
drop of the inoculation fluid on the surface by means of a glass rod. 
The nitric acid reaction appears about the fifth or sixth day. To 
render the colonies apparent on the milky surface of the plate, a solution 
of ammonia is used. A couple of drops of a 10 per cent, solution are 
placed in two small excavations cut in each plate. 
For isolating nitrate-formers, the following media are used in the 
Imperial Institute at St. Petersburg. A liquid medium is composed of 
natr. nitros. (Merck) 1 grm. ; natr. carbon, ustum 1 grm. ; kal. phosphor. 
0 * 5 grm. ; natr. chlorat. 0 * 5 grm. ; ferrum sulph. 0 * 4 grm. ; magn. 
sulph. 0 * 3 grm. ; aq. destil. 1000 grm. 
A solid medium has the following composition : — Natr. nitros. 
(Merck) 2 grm. ; natr. carbon, ustum 1 grm. ; kal. phosph. a trace ; 
agar 15 grm. ; water 1000 grm. 
Demonstrating the Spirilla of Geese.| — Dr. J. Cantacuzene states 
that he obtained good results from the following method : — (1) Small 
* Central bl. Bakt. u. Par., 2 te Abt., v. (1899) pp. 537-49 (1 ph). 
t Ann. Inst. Pasteur, xiii. (1899) pp. 534-5 (2 pis.). 
