378 SUMMARY OF CURRENT RESEARCHES RELATING TO 



(4) Staining and Injecting. 



Staining Malaria Parasites.* — G. Giemsa contends that methylen- 

 azur is the effective agent in the solutions used for staining malaria 

 parasites, and that the part played by the eosin salts of methylen-blue 

 and metbylcn-violet has been much overrated. He mixes together 

 19 ccrn. of 0*005 p.c. eosin (Hochst) solution and 1 ccm. of 0*08 p.c. 

 solution of agar. The staining takes only a few minutes, and the pre- 

 parations only require to be washed in water. 



Method for Washing, Staining, and Dehydrating Small Speci- 

 mens. "]■ — The apparatus used by J. E. Slonaker for dehydrating, 

 washing, or staining small objects consists of a circular board about 

 12 in. in diameter, on the radii of which are fastened a number of 

 trough-like tin pieces for holding suitable sized vials securely. The 

 wheel is made to revolve slowly (about once or twice a minute) in a 

 vertical plane by any desired method, the writer making use of a water 

 motor for the power, and an old clock gear to reduce the speed. 



Intra vitam Staining of Fungi4 — J. Plato and H. Guth record the 

 appearances observed from intra vitam staining of Penicillium brevi- 

 caule and some Trichophyta. The staining solution consisted of neutral 

 red 1 to 50,000 — 10C,000 physiological salt solution ; when used so 

 much KHO was added as to impart to the neutral red solution an orange- 

 yellow hue. Pieces cut out of the margin of a 3 to 4 days' old culture 

 were placed in flat capsules containing some of the staining solution. 

 The piece was examined under a low power from time to time, and 

 when the ends of the filaments were found to be stained (10 minutes to 

 1 hour) the piece of culture was placed on a slide and then a cover-glass 

 applied, some distilled water being run under to prevent the preparation 

 from drying. 



New Method for Staining in Bulk.§ — A. Spuler uses finely 

 powdered cochineal boiled in distilled water, and after filtering evapo- 

 rates nearly to dryness. The mass is then treated with alcohol, filtered 

 and evaporated, after which it is dissolved in distilled water. In this 

 solution the pieces are incubated for 24 hours or longer. They are then 

 washed, and mordanted in a dilute iron-alum bath by which the colour is 

 changed from red to black. After having been thoroughly washed the 

 pieces are imbedded and sectioned. 



For projection purposes this procedure is extremely suitable as the 

 outlines are well defined and the colour black. 



(51 Mounting, including Slides, Preservative Fluids, &c. 



Preserving and Mounting Rotifera.|| — C. F. R,ousselet first isolates 

 the rotifers, picking them up under a dissecting Microscope with a fine 

 teat-pipette and then placing them in a watch-glass half full of perfectly 



* Centralis. Bakt., 1" Abt. Orig., xxxi. (1902) pp. 429-30. 

 t Journ. App. Micr.. v. (1902) pp. 1645-6 (1 fig.). 



t Zeitschr. f. Hygiene u. Infekt., xxxviii. (1901) p. 319. See Centralbl. Bakt., 

 l te Abt, xxxi. (1902*) p. 190. 



§ Deutsche Med. Wochenschr., xxvii. (1901) ver.-beil., p. 116. 

 1| Knowledge, xxr. (1902) pp. 68 and 91. 



