SOME OTHER HISTOLOGICAL METHODS. 449 



solution (MAX FLESCH, Zeit. f. wiss. Mik., v, 1, 1888, 

 p. 83). 



GKIESBACH also (op. cit., p. 328) prefers osmic acid, not 

 only as being a first-rate fixing agent, but because it can be 

 combined with certain stains without decomposing them. 

 He mentions methyl green, methyl violet, crystal violet, 

 safranin, eosin ; Saurefuchsin, rhodamin, and iodine in potassic 

 iodide. 



Rossi (Zeit. f. wiss. Mik., vi, 4, 1889, p. 475) advises a 

 mixture of equal parts of 1 per cent, osmic acid, water, and 

 strong solution of methyl green, permanent mounts being- 

 made by means of glycerin cautiously added. 



EWALD (Zeit. Biol., xxxiv, 1897, p. 257) mixes three to 

 four drops of blood of amphibia or reptiles with 10 c.c. of a 

 solution of 0'5 per cent, osmic acid in 0'5 per cent, salt 

 solution (for mammals 0'6 to 0'7 per cent, salt), siphons off the 

 supernatant liquid after twenty-four hours with his capillary 

 siphon ( 3, p. 4), and substitutes water, alum-carmine, etc., 

 and lastly, 50 per cent, alcohol. 



See also AENOLD, Arch. path. Anat., cxlviii, 1897, p. 479. 



The mercurial liquids of Pacini ( 405) used to be con- 

 sidered good. HAYKM (op. cit.; see also Zeit. f. wiss. Mik., 

 vi, 3, 1889, p. 335) has the following formula : sublimate 

 0'5, salt 1, sulphate of soda 5, and water 200. This should 

 be mixed with blood in the proportion of about 1 : 100. 

 Eosin may be added to it. L6 WIT'S formula (Sitzb. k. Akad. 

 Wiss. Wien, xcv, 3, p. 129; Zeit. wiss. Mik., vi, 1, 1889, 

 p. 75) consists of 5 c.c. cold saturated sublimate solution, 5 

 grins, sulphate of soda, 2 grms. salt, and 300 c.c. water. 

 Mosso finds, however, that both of these are too weak in 

 sublimate. 



Of course other well-tried fixing fluids, such as Flemming's 

 solution, or Hermann's, may also be used for blood. 



LAVDOWSKY (Zeit. f. wiss. Mik., x, 1, 1893, p. 4) describes some remark- 

 able results obtained by fixing with 2 per cent, iodic acid, and staining with 

 Neu-Victoriagriin, methyl violet 6s, or gentian violet, a process which is 

 said to reveal the presence of nuclei in elements generally considered to be 

 apyrenematous. 



DUBOSCQ (Arch. Zool. Exper., vi, 1899, p. 481 ; Journ. 

 Roy. Mic. Soc., 1899, p. 545) uses (for blood of Chilopoda) 



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