452 CHAPTER XXXIIf. 



For details as to the staining reactions of the granules of leucocytes, see- 

 the literature quoted in previous editions, and see also particularly the 

 critique in FISCHER'S " Fixirung, Fdrbung und Ban des Protoplasmas" 

 (Jena, G. Fischer, 1899), the outcome of which is that the supposed speci- 

 ficity of the reactions is a mere mare's nest. 



809. Demonstration of Blood-plates of Bizzozero (KEMP, Studies 

 from the BioL Lab. Johns Hopkins Univ., May, 1886, iii, No. 6; 

 Nature, 1886, p. 132). A somewhat large drop of blood is 

 placed on a slide, and quickly washed with a small stream of 

 normal salt solution. The blood-plates are not washed away, 

 because they have the property of adhering to glass ; and on 

 bringing the slide under the microscope they will be seen in 

 large numbers. If it be desired to make permanent pre- 

 parations of them, they should first be fixed. This is done 

 by putting a drop of osmic acid solution on the finger 

 before pricking it. 



For BIZZOZERO'S methods for the numeration of these elements and for 

 the study of their regeneration, see his paper in Festschr. R. Virchow 

 gewidm., etc., 1, 1891, p. 459 ; or Zeit.f. wiss. Mik., ix, 2, 1892, p. 229. For 

 his stain for them see 808. 



For the application of some digestion methods to the study of blood-plates, 

 see LILIENFELD, Arch. f. Anat. u. Physiol, Physiol. Abth., 1892, p. 115 ; 

 or Zeit.f. wiss. Mik., ix, 3, 1893, p. 363. 



For methods for obtaining large quantities of blood-plates, see DRUEBIN 

 Zeit.f. wiss. Mik., x, 4, 1893, p. 493. 



For BRODIE and RUSSELL'S numeration methods see Journ. of PJiysiol.. 

 xxi, 1897, p. 390; Zeit.f. wiss. Mik., xiv, 1897, p. 392. 



For DETERMANN'S, see ibid., xvi, 1899. p. 86. 



810- WEIGERT'S Fibrin Stain (Fortschr. d. Med., v, 1887, 

 No. 8, p. 228 ; Zeit. /. wiss. Mik., iv, 4, 1887, p. 512). Sec- 

 tions (alcohol material) are stained in a saturated solution of 

 gentian or methyl violet in aiiilm water (p. 203). They 

 are brought on to a slide and mopped up with blotting- 

 paper, and a little Lugol's solution ( 88) is poured on to 

 them. After this has been allowed to act for a sufficient 

 time they are differentiated and cleared in anilin oil u-ithout 

 previous dehydration with alcohol. They are simply mopped 

 up with blotting-paper, and a drop of anilin is poured on to 

 them. The anilin soon becomes dark, and is then changed 

 for fresh once or twice. When this has been done, the 

 anilin is thoroughly removed by means of xylol, and a drop 



