ZOOLOGY AND BOTANY, MICROSCOPY, PJTC. 773' 



tage to warm to 25° C. The sections are washed in acidified water, and 

 then kept for at least 24 hours in a 50 p.c. watery solution of glycerin. 

 They are then brought into Canada balsam through alcohol and chloro- 

 form. This method differentiates non- woody cells, as those of the bast- 

 parenchyma and medullary tissue. 



Vital Staining of Micro-organisms. — B. Romanoff * has studied 

 granules in bacteria, moulds and yeasts, by means of vital staining with 

 methylene-blue and neutral red. The property of the latter to lose its 

 colour in the presence of alkalies, and to regain it with acids, makes this 

 stain a delicate indicator of the reaction of the cytoplasm in different 

 parts of the same cell. He finds that in yeast there are granules 

 other than fat and glycogen staining with neutral red. To demonstrate 

 this he grew it in a medium poor in nutrient elements, containing 

 mag. sulph. ; pot. phosph.; sod.chlorid. ; asparagin ; peptone. Yeast so- 

 cultivated contained no glycogen and a minimum of fat. 



Vital Staining of Blood-Plates in Man with " Brillantkresyl- 

 blau." — G. Puchberger f stains blood-plates with this dye in less than 

 a minute, and, after the lapse of about a quarter of a hour, a hyaline 

 substance separates itself in spherical form (Hyalomer), but continues 

 connected by a constriction with the remaining, also circular, stained 

 part of the cell (Chromomer). The nuclei of the lymphocytes and the 

 granules of the leucocytes stain in a similar manner, but not so the 

 nuclei of the polynuclear or the large mononuclear cells. In leukaemia 

 are found large blood-plates the size of lymphocytes. These behave 

 in the above described manner. Similar changes occur in lymphocytes, 

 the nuclei of which separate from the protoplasm. The statement that 

 the chromomer of blood-plates corresponds to the nucleus requires 

 proof. 



Iron Carmalum.J — J. G-. de Groot suggests the following as a useful 

 modification of Mayer's Carmalum. (1) Carminic acid (F. A. Kahl- 

 baum, Berlin So.), 1 grm. ; (2) ammonio-sulphate of iron, ■ 1 grm. ;• 

 (3) alum, 5 grm. ; and (4) distilled water, 200 c.cm. To prepare the 

 stain, dissolve No. 1 with warmth in 20 c.cm. water ; add No. 2 and dis- 

 solve ; add 180 c.cm. water and warm ; stir in No. 3 ; cool and filter ; 

 add two drops hydrochloric acid, and a crystal of thymol. 



It can be used both for bulk staining and for sections. 



Modification of the Uranium Carmine Staining of Schmaus.— 

 E. Chilesotti § has devised the following method for staining axis cylinder 

 with carmine. 1 grm. soda carmine (Grubler) is rubbed up with • 5 grm. 

 uranium nitrate. The mixture is boiled for half an hour with 100 c.cm. 

 water, then filtered, and before use. a little 1 p.c. hydrochloric acid 

 alcohol is added to the solution (\5-l c.cm.). Sections hardened in 

 Muller stain in this in 5-10 minutes, those hardened in formalin in 

 15-20 minutes, in Weigert's neuroglia mordant in 30-GO minutes, and 



* Bull. Soc. Imp. Natur. Moscow, 1903. pp. 581-2. 



t Virchow's Archiv., 1903, Heft 2. See Centralbl. Bakt. Kef., xxxiii. (1903) p. 545. 

 t Zeit. Wiss. Mikr.. xx. (1903) pp. 21-3. 



§ Centralbl. Allg. Path., 1902, p. 193. See also Zeit. Wiss. Mikr., xx. (1903) 

 pp. 87-88. 



