194 QUARTERLY CHRONICLE OF MICROSCOPICAL SCIENCE, 
lial layer, forming no connections in the former; and 
the same thing is seen when the epithelium is removed 
by careful maceration. On the other hand, the epithelial 
cells he finds to be connected with large stellate cells of the 
sub-epithelial layer. (The sub-epithelial tissue is accord- 
ingly not nervous, as asserted by Exner.) 
With regard to the connection of the olfactory cells 
with fibres of the olfactory nerve, Cisoff was able to 
demonstrate this in a few well-marked instances, and 
even fine nerve bundles were seen thus connected with 
“olfactory cells.” The latter cells were never seen in 
connection with the sub-epithelial tissue. The central 
process of the olfactory cell has, as described by Max 
Schultze, a striking resemblance to a varicose nerve- 
fibre. The general conclusion is that Schultze’s description 
is in the main correct, though somewhat diagrammatic. The 
observations were made on the frog and the rabbit. The 
chief reagents used were chloride of gold, diluted Miiller’s 
fluid, and as a staining material hematoxylin. Paschutin 
(‘ Leipzig Physiolog. Arbeiten,’ 1873, p. 41) had equally 
denied the nervous character of Exner’s sub-epithelial net- 
work, while confirming its connection with the epithelial 
cells. Both observers agree in maintaining Schultze’s dis- 
tinction of epithelial and olfactory cells. 
2. Termination of the Gustatory Nerve.—E.Sertoli(‘Gazetta 
Medico-Veterinaria,’ anno iv, abstract in ‘ Centralblatt fur 
die Medicin. Wissenschaften,’ no. 55, 1874) investigated the 
papilla foliata of the tongue of the horse. For the inves- 
tigation, the author employed a very interesting modification 
of the gold method. Small pieces of fresh tissue were placed 
in a relatively large quantity of gold solution (4 to 4 per 
cent.) and allowed to remain therein for eighteen or twenty- . 
four hours, then washed out with water, and placed for 
twenty-four to forty-eight hours in a 2 per cent. solution of 
bichromate of potash. They were then washed out with 
water and placed in absolute alcohol, in which they were 
completely hardened, and in which the colouring already 
begun in the bichromate of potash became perfect. The 
colouring can be accelerated by exposing the preparation in 
bichromate of potash to a temperature of 30° Cent. (86° 
Fahr.). The papilla foliata is very richly supplied with 
nerves. In the subepithelial connective-tissue the nerves 
form a very dense network, to end in the two following 
ways: (1) in the gustatory bulbs, which are present in ex- 
traordinarily large numbers in the folds and furrows of the 
papilla foliata; (2) in an intra-epithelial network of fine 
