ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
699 
slightly acid, then in neutral SO per cent, alcohol, and transferred to dis- 
tilled water. They were then transferred to 0*25 per cent, solution of 
gentian-violet in water for 2-4 hours ; then washed out successively in 
2 per cent, aqueous solution of Griibler’s orange G, 1 per cent, solution 
of orange G in 50 per cent, alcohol, and methylated spirit ; dehydrated, 
and cleared in clove oil. (2) Renaut’s hsematoxylic eosin for alcohol 
material. The sections were left all night in a solution of 2-3 drops 
orseillin extract diluted with 100 ccm. of water ; then rinsed, and placed 
in a very dilute solution of Renaut’s hrematoxylic eosin in 0 * 1 per cent, 
aqueous solution of potash-alum, washed with tap-water (to keep them 
alkaline), and the orseillin stain washed out slowly by dilute alcohol. 
Staining of Fungi.* — Mr. H. Wager recommends the following 
methods, especially for observing the sexual organs ( Cystopus ). The 
most useful fixing and hardening reagent is corrosive sublimate. The 
pieces of tissue are then well washed in water, transferred to 30 per 
cent, spirit, 50 per cent, spirit, and 70 per cent, spirit, and finally to 
90 per cent, spirit, about 2 or 3 hours in each. They may now be 
saturated en bloc and imbedded in paraffin, or they may be first imbedded 
in paraffin and the sections stained on the slide (the latter preferable). 
For imbedding previously to staining they are transferred to absolute 
alcohol for half an hour, then to a mixture of alcohol and xylol, and are 
finally placed in melted paraffin. The staining solutions used are as fol- 
lows : — (1) 50 percent, spirit, 4 vols. ; glacial acetic acid, 1 vol. ; (2) to 
solution (1) enough nigrosin is added to make it opaque in the bottle 
and transparent in a half-in. layer; (3) to solution (1) enough nigrosin 
is added to make it blue, but transparent, in a layer 2 in. thick; 
(4) 50 per cent, spirit, to which a small quantity of (2) is added to 
make it quite light blue; (5) Mayer’s alcoholic solution of carmine. 
The sections are placed for 5 or 10 minutes in the mordanting solution 
(4). They are then placed in Mayer’s carmine for a few minutes until 
they become stained distinctly red, then washed in 30 per cent, spirit 
in solution (3). If a deep stain is required, use solution (2). 
(5) Mounting 1 , including Slides, Preservative Fluids, &c. 
Preserving Embryological Material.! — Prof. A. A. W. Hubrecht 
adopted the following method for collecting and despatching embryo- 
logical material from the Dutch East Indies to Utrecht. The animals 
were killed with chloroform and then cut up. The uterus was removed 
and placed in picrosulphuric acid, prepared according to the following 
formula : 100 volumes of saturated aqueous picric acid were mixed with 
2 volumes of sulphuric acid. The solution was filtered and mixed with 
Water in the proportion of 1 part of the solution to 3 parts of water. 
In this mixture the parts cut out were placed ; after 10 to 15 minutes, 
the fluid having become cloudy, fresh acid solution was used. In this 
the preparations remained not less than 8 and not more than 24 hours. 
They were then transferred to 70 per cent, alcohol, and after 1 or 2 days 
to 90 per cent, alcohol. 
* Ann. Bot., x. (1896) pp. 312-4. 
t Naturk. Tijdschrift voor Nederl.-Indie, Deel 54, p. 90. See Zeitsehr. f. ang. 
Mikr., ii (1896) p. 111. 
