1092 General Notes. [October, 
In a great number of cases it may be regarded as a 
advantage of the celloidin that it penetrates the tissues tho- 
roughly and yet remains pellucid, so as to be more or less invisi- 
ble in the specimen. This quality can be made use of in another 
direction for the purpose of soaking specimens which are too 
brittle to be cut after hardening alone, We may make use of cel- 
loidin in a similar way to the gum arabic mentioned above. 
minute normal and pathological anatomy of the lung in particu- 
lar will derive great advantage from such a proceeding. Indeed, 
we are not able to get a perfect idea of the changes produced by 
pneumonia if we do not by this method or by the following (with 
paraffine) prevent the loss of a great part of the exuded su 
stances which in this disease lie loose in the alveolar cavities 
The study also of micro-organisms in the lung will derive great 
benefit from the celloidin method, and it will be very welcome to 
many to know that the tissues imbedded in celloidin may be 
stained with the different fluids, ammonium-carmine, alum-cat- 
mine, borax-carmine, hematoxylin, analine colors and various 
others. The reaction of acids and alkalies, particularly acetic 
acid and solution of potash is, moreover, not interfered with. 
And further, we are able to color the object before imbedding 
with all staining fluids which are not soluble, or only little soluble, 
in alcohol and ether. 
After staining and cutting the sections may be mountes = 
glycerine and various other fluids. Mounting in Canada noe 
requires, however, some precautions on account of the ee 
character of the celloidin. Absolute alcohol and oli of r 
should be avoided and replaced by alcohol of ninety-six pef effet: 
and by oleum origani. This is, at least the advice of Schi a 
decker and Professor Thoma has had no occasion to be dissa a 
fied with the result. é another 
The efforts of Bütschli and Blochmann’ have gm ae tt 
. we . 2 . in i ; de ji 
splendid-imbedding mass? paraffine dissolved stechii Was 
ecimens down © 
0.002™™ This method seems particularly ada re ats 
be recommended. The long-known ammonium 
occasionally useful. : 
Dr. M. Schulgin} in order to obviate the incon 
the same portion of the knife has always to be used, 
1 Biol. Centralbl., 1 (1881), pp. 591-2, See this journal, H (18623 i 
* The credit of introducing this mass belongs to Dr. Giesbrecht. 
*Zool. Anzeig., vI (1883), p. 21. 
venience that 
has hada 
