~ 
_ be recommended in such cases. 
5 ron J » 
158 BOTANICAL GAZETTE. [ June, 
The paraffin-imbedding process in botany.—Within a few months 
there have appeared two articles! on this subject, and as the writer has 
been devoting some attention to it lately it may be of interest to some of 
the readers of the GAzErTe to state briefly the results obtained. It was 
found convenient to combine to some extent the methods given in the 
articles referred to, as neither was found in all respects satisfactory, and 
some simplifications of the processes were made which were found 
advan u 
rant a very strong recommendation of the imbedding process where the 
sectioning of very delicate tissues is necessary; indeed, when the results 
thus obtained are compared with the imperfect and uncertain methods 
ordinarily used in such work, no one who has used both will, I think, 
esitate as to their comparative merits. With the firmer plant tissues 
there is usually no necessity for any imbedding process, and owing to 
the time and care necessary to successfully apply this method it is not to 
n regard to th 
gag POD co He} 1 J ond Mail disagree, the 
former recommending alcohol, which Moll does not consider satisfactory; 
prefering chromic acid or the mixture of chromic, osmic and acetic acids 
walls are present it is extremely difficult to get the paraffin to penetrate 
such membranes, whereas it is much easier where fixing solutions con- 
taining chromic acid are employed. A practical illustration of this was 
found in the very thick-walled macrospores of Pilularia. 
_Allter the material js thoroughly hardened, and in the case of alco- 
holic material allowed to remain for 24 hours in borax-carmine, it is 
treated as described b Schénland? For the gradual transfer from 
Soe bag absolute alcohol the Schultz apparatus? was found most 
ie The following method of imbedding was found practical and simple: 
_ mal’ paper box is made by taking a strip of pretty firm paper and 
8 a paper cylinder can, of course, be slippe f 
: ° DOX 18 completed by cutting out a round piece of paper 0 
1Sehé 2. 
2L, peng Bot, Centralblatt, No. 22, 1887, Moll, Bor. Gazerre, Jan. 1888. 
gate also Bor. Gazerre, July 1887. : 
trasburger, Bot. Prak., 11 Edit. 
