ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
345 
Staining Vegetable Sections.* — Prof. F. D. Kelsey recommends 
that vegetable sections should be stained with pigments dissolved in 
clove oil. After staining, remove to pure clove oil or Gage’s fluid, and 
mount in balsam. It is hardly necessary to point out that the section 
must be perfectly dehydrated before it is immersed in the clove oil 
stain. A dilute clove oil stain acts better than a concentrated one. 
Method of Staining the Malaria Flagellated Organism.f — Dr. P. 
Manson has succeeded in staining the flagellated malaria parasite by the 
following method, which shows the pigment and certain details of struc- 
ture with ease and certainty. Thirty or forty strips (3 by 1J inches) 
of thick blotting-paper, each having an oblong hole (1 by inch) cut 
lengthwise in its centre, are prepared. They are then slightly moistened 
with water and laid in rows on a sheet of window glass. A droplet of 
blood, the size of a large pin’s head, is then obtained by puncturing 
the finger of a person in whose blood the crescent form of the malaria 
parasite abounds. A Microscope-slip is then breathed on once, and the 
droplet of blood dabbed on the centre of the breathed-on surface. The 
blood is then spread out with a needle so as to cover an area of f by 
h inch, and the slip immediately inverted over a blotting-paper cell. 
The slip is then pressed down, care being taken to prevent the blood 
coming in contact with either the wall of the cell or the floor of what is 
now a very perfect moist chamber. In from half to three-quarters of an 
hour the slips are removed, and dried by gently warming them over a 
spirit-lamp. When dry, the films are fixed with absolute alcohol. 
After five minutes the alcohol is dried off, and a few drops of acetic 
acid (10-20 per cent.) are laid on the film, and left long enough to dis- 
solve out the haemoglobin. The slips are then washed in water and 
dried. After this they are stained with 20 per cent, phenol-fuchsin, the 
stain being dropped on and the slip covered with a watch-glass. After 
six hours it is washed off, the slide dried, and a cover-glass applied with 
xylol-balsam. Most of the slides will show numbers of spheres and 
several or many well-stained flagellated bodies. Very few crescents 
remain untransformed. If the slips are removed and dried in from five 
to ten minutes after being placed on the blotting-paper cells, only 
crescents, ovals, and spheres will be found ; if left for more than three- 
quarters of an hour, free flagella and spent pigment may be found. 
Staining Diphtheria Bacilli.^ — Dr. C. F. Craig states that Crouch 
of Denver has found that, if 24 hours old culture of diphtheria be treated 
for a few seconds with 1 per cent, methyl-green solution, the majority 
of the bacilli will be faintly stained green, and will show at both ends a 
well defined round body of a distinctly red colour. The following solu- 
tion was found to be very serviceable : — 1 per cent, methyl-green, 5 parts ; 
1 per cent, solution of dahlia, 1 part ; distilled water, 4 parts. Only a 
second is required for staining ; if left in longer, the staining is too intense. 
Combination of Weigert’s Fibrin Method and the Tubercle Bacillus 
Stain.§ — Herr Roloff stains tubercle bacilli and fibrin in the same section 
* The Microscope, v. (1897) p. 69. 
t Biit. Med. Journ., 1897, ii. pp. 68-70 (15 figs.). 
X Trans. Amer. Micr. Soc., xviii. (1897) pp. 274-5. 
§ Arb. a. d. Pathol.-Anat. Inst, zu Tubingen, ii. (1896) p. 261. See Centralbl. 
Bakt. n. Par., l te Abt., xxi. (1897) p. 749. 
