ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
79 
Growing-Cell.* — Dr. A. M. Edwards describes the growing-cell 
which he has used in the examination of Bacillariaceae. In a piece 
of plate glass, a quarter of an inch thick and three inches square, a 
hole about two inches in diameter is cut. The piece of glass thus 
bored through forms the box of the growdng-cell. A bottom is formed 
of ordinary plate glass soldered on. The cover is also of ordinary 
plate glass, loose on the cell. It has a minute hole drilled in it to 
form a communication for the water in the body of the cell to the 
cover of the object. This is an ordinary round cover placed upon 
the plate glass. 
Lately, in the observation of the actions on Bacillariacese of the 
change of water from fresh to salt, the author has used a simpler con- 
trivance, viz. a small bottle with flat sides cemented to an ordinary 
slide. The bottle is closed by a cork, but has a small hole drilled 
in it to let the water communicate with the interior and the Bacilla- 
riacese. 
Cultivation Medium for Ringworm .Fungi.f — Dr. T. C. Fox and 
Dr. F. R. Blaxall recommend the following medium for cultivating 
ringworm fungi, as it gives consistent and reliable results. lit is 
called maltose-potato-agar. It is made by preparing a decoction of 
potatoes, 1/2 a kilogram of powdered potato to a litre of water, steaming 
this well till of a light brown colour, then straining through a fine 
cloth. To the filtrate is added 1*5 per cent, agar, and 3 per cent, 
pure maltose. The medium has a slightly acid reaction. On it 
development is quick, the fungi giving a visible growth from the third 
to the fifth day. 
Cultivating Pathogenic Schizomycetes on Media containing Supra- 
renal Extract.^ — Dr. N. Wroblewski records three series of experiments 
made with cultivation media containing juice from supra-renal bodies for 
the purpose of ascertaining the effect on certain bacteria. A fresh 
bullock’s supra-renal body was minced and pulped and then boiled for 
2 hours with water and alkalinised with soda. The extract thus 
obtained was mixed with an equal bulk of agar (2*5 grm. agar, 
6 grm. glycerin, 1 grm. common salt, to 100 of water), sterilised, 
filtered two or three times to get rid of any precipitate, and finally 
sterilised again. After that it was kept at 36° for a couple of days. 
Extract made as before, mixed with an equal quantity of 20 per cent, 
gelatin, formed the medium for series 2, while series 3 was made 
with supra-renal bouillon. The proportions used were the same as in 
ordinary beef broth (0*5 kgrm. meat, 15 grm. pepton, 5 grm. com- 
mon salt, 3 grm. of soda to 1 litre of water), but supra-renal body 
was substituted for the meat. 
These experiments showed that media containing supra-renal extract 
were favourable to some bacteria, and decidedly unfavourable to others, 
and also indicated that they might be used to distinguish between 
closely allied species such as B. coli com. and B. typhosus , when grown 
on supra-renal agar, or by difference of colour arising in course of 
cultivation, as with V. cholerse asiat. 
* Amer. Micr. Journ., xvii. (1896) pp. 346-9. 
f Brit. Journ. Dermatol., viii. (1896) p. 308. 
X Centralbl. f. Bakteriol. u. Parasitenk., l te Abt., sx. 1896, pp. 528-35. 
