ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
885 
It will be seen that the most satisfactory results were obtained by 
killing in picro-hydrocliloric acid, and preserving in method 6. 
Injection of a Mammal previous to Section-cutting.* — Mr. H. 
Meller in giving a demonstration of his method, chose a rabbit and killed 
it by an injection of potassium cyanide into the mouth. “ The apparatus 
and injecting mass being ready, immediately the animal was dead the 
thorax was opened and the apex of the heart cut off, so as to lay open the 
right and left ventricles ; through the left ventricle a glass cannula was 
inserted into the aorta and fastened by a ligature tied round this vessel. 
To the glass cannula an ordinary indiarubber enema was attached, and 
by this means a continual stream of warm normal saline solution was 
driven through the vascular system, the blood and saline solution 
escaping by the right ventricle ; as soon as this ran out clear, an ordi- 
nary glass syringe, charged with a gelatin mass coloured blue, was 
substituted for the enema. As soon as the injection began to pass 
out of the right ventricle a broad ligature was tied tight round the 
heart, just above the cut end, thereby preventing any more escape of 
fluid by the right ventricle. The cannula was still retained in the 
aorta, but the syringe being changed for another containing a gelatin 
mass coloured red, and not quite so fine as the preceding, this was 
injected into the arterial system so as to drive the first injection as 
completely as possible into the veins. During the injection everything 
was kept under warm salt solution, and when the operation was com- 
pleted the animal was laid aside for one or two hours to allow the mass 
to solidify. The demonstrator then explained that at the completion of 
this time the parts could be prepared for section-cutting, or the animal 
preserved in 90 per cent, spirit or other preservative. The following are 
the formulae for the various solutions used during the demonstration : — 
Normal saline solution : salt 7 * 5 grm., water 1000 ccm. Gelatin mass : 
soak gelatin in water till soft, then melt over water-bath. Red in- 
jection : gelatin mass mixed with carmine dissolved in ammonia. Blue 
injection : gelatin mass mixed with freshly precipitated Prussian blue.” 
Cl) Collecting: Objects, including 1 Culture Processes. 
Bacteria-fishing Apparatus- 1 — Dr. Schrank fishes out a specimen 
from a particular colony for inoculation purposes by means of a needle 
fitted to a metal case, like an objective, in which the needle is substi- 
tuted for the lens. With a low power the particular colony is focused 
at the intersection of cross-threads, and then the lens replaced by the 
needle, which is lowered down until it reaches the colony. The colony 
is again observed in order to make sure if the needle has touched it. 
Influence of Filtration on Liquids containing Microbic Products.J — 
M. Arloing has made some experiments to ascertain what effect earthen- 
ware filters have on the composition of fluids containing microbic 
secretions. The liquid used was the juice of beetroot, after it had been 
fermented in silos. This fluid was passed through new Chamberland 
filters, and it was found that a considerable percentage of proteid 
* Journ. Brit. Dental Assoc., xiii. (1892) pp. 581-2. 
t Zeitschr. d. Allgem. Oesterr. Apothekervereines, 1892, No. 14. See Centralbl. 
f. Bakteriol. u. Parasitenk., xii. (1892) p. 312. 
X Comptes Rendus, cxiv. (1892) pp. 1455-7. 
