806 General Notes. -o py 
by means of shellac, and also Dr. Gaule’s method of using alco- 
hol (50-60 per cent) for the same purpose. In the employment 
of either of these methods, the object must be stained zx toto. Dr. 
Frenzel now offers a method which allows one to color the sec- 
tions after they have been fixed on the slide. Instead of shellac 
a solution of gutta-percha in chloroform and benzine is used. 
The solution must be filtered until it is clear and almost colorless, 
and must not be made so thin that it will flow quickly on the 
slide. The fluid is put on with a brush and allowed to dry be- 
fore the sections are placed. If the object is imbedded in paraf- 
fine or a paraffine mixture (e. g., four parts paraffine and one part 
vaseline), the sections are smoothed out by the aid of a brush 
wet in alcohol, and then exposed to a temperature of 35° to 50°C. 
for five to ten minutes, in order that the gutta percha may be- 
come sticky; they are then left for five to ten minutes in the alr, 
and finally placed in a vessel containing absolute alcohol heated 
t i 
E 
os 
i=) 
oO 
z 
M 
| 
ct 
> 
a 
= 
O 
e] 
= 
[e] 
= 
g 
o 
O 
O 
= 
(g) 
wn 
n 
es] 
ct 
io 
= 
eS 
or 
is) 
O 
pat 
5 
fes] 
e 
o 
oO 
ch 
g 
3 
aisam. 
If the object is imbedded in celloidin, as is now frequently 
tion. After the sections have dried on, they may be staim 4 
washed and transferred to absolute alcohol as before. The appli 
cation of clove oil before the balsam dissolves the celloidin. 
_ THE Hertwics’ Maceratinc FLurp.!— For the isolation of 
tissues in the Ccelenterates, Oscar and Richard Hertwig rec?” 
mend the following mixture : 
MN hs akg Pak cevccucdv cases a A seasoned r part. 
a ee E EN ee AE OET EFEO EADE 1 i 
aa ao E A E CLE ome E E ee 
# 1000 
eee ee wonee 
| poate annae se e cells, 
By means of this fluid not only the nerve cells, musc! hy ls 
may be easily recognized, but also the tissues in the form, 
lamellæ may be separated and studied as a whole. 
tissue or whole animals are left in the mixture five to ten 
tic 
oe etal for severai hours in one-fifth per Be write 
acid. ae l 
e macerated parts can be further prepar t once before 
preparation with needles. In the first case picrocarmine 1$ 
wards colored on the slide ; or they can be colored a is used, 
1 Jenaische Zeitschrift, xtiT, p. 462, 1879. 
