278 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
during the height of the paroxysm, and the patient should not have taken 
any quinine for some time. The tip of the finger, having been properly 
cleaned, is pricked with a lancet, and the drop of blood is then placed 
between two cover-glasses. Fresh blood is best examined by daylight 
and with high dry powers. The flagella will be seen most frequently 
on the edges of the pigmented round free corpuscles. If a dry prepara- 
tion is to be examined, the cover-glasses are drawn apart, the blood 
allowed to dry, and then the cover-glass is drawn thrice through the 
flame. 
The preparations may be examined unstained, but the author prefers 
to stain with a saturated aqueous solution of metliylen-blue, before 
using which the cover-glass must be washed with equal parts of alcohol 
and ether. In this way the nuclei of the white corpuscles are stained 
dark blue, while the round bodies, either free or adhering to the red 
corpuscles, are pale blue, and the growing corpuscles scarcely at all 
coloured. 
Hydroxylamin as a Paralysing Agent, or Prefixative, for small 
animals.* — Dr. B. Hofer recommends hydroxylamin for paralysing 
small animals, as this substance and its hydrochlorate or sulphate possess 
a well marked paralysing action on contractile elements. 
In commerce it is obtained as the crystalline hydrochlorate; of this a 
1 per cent, solution in water is made, and this is then rendered neutral 
by the addition of carbonate of soda. For dissolving the salt, spring, 
pond, or sea water must be used, and not distilled water. It is not 
advisable to have excess of the carbonate of soda, as this renders the 
solution too strongly basic and also less stable. 
The animals having been palsied in this neutral solution of hydroxyl- 
amin, the next step is to fix them : for this purpose alcohol, picric 
and acetic acid, or a mixture of these acids, are recommended, as osmic 
and chromic acid, sublimate, the chlorides of gold and platinum are too 
easily reduced. The author gives several special examples of the action 
of this fluid. It is sufficient to state that it is used in 0* 1 to 1 percent, 
solution, the most useful strength being 0 * 25 per cent. From the 
examples quoted, e. g. Stentor cseruleus , Spirostomum teres , Carchesium 
polypinum , Hydra grisea , Bunodes gemmacea , Dendrocoelum laeteum , 
Hirudo medicinalis, Rotatoria and Mollusca, it is obvious that this 
reagent possesses a specific paralysing action on the contractile elements 
of the lower animals, and that its use as a preliminary to the permanent 
fixative is a distinct advantage. The length of time needed to produce 
the paralysing action of course varies with the size of the animal and 
the strength of the solution. 
Preparation of Aleurone-grains.f — M. Y. A. Poulsen calls attention 
to Overton’s method of preparing and fixing the aleuron e-grains in the 
endosperm of Bicinus. By plunging an absolute alcohol section in an 
aqueous solution of gallo-tannic acid, crystalloids are made to imbibe 
the acid and take a brown colour ; they are then placed in a 1 per cent, 
solution of osmic acid, washed in distilled water, and preserved in 
glycerin. This method depends on the production of metallic osmium 
* Zeitschr. f. Wiss. Mikr., vii. (1S90) pp. 318-2G. 
f Rev. Gen. de Bot. (Bonnier), ii. (1890) pp. 547-8. 
