192 ClIAl'TEli XV. 



present this colour Las chiefly been employed for intrit-vitam 

 staining. Tadpoles kept for a day or two in a solution of 1 : 

 10,000 or 100,000 absorb so considerable a quantity of the 

 colour that all their tissues appear of a dark red. The stain 

 is limited to cytoplasmic granules (Bhelich), and to the 

 contents of mucus cells (G-aleotti). 



According to Bhelicq and Lazaeds {Spec. Pathol, und 

 Therapie, herausgeg. von Nothnagel, viii, I, 1898, p. 1 ; 

 Zeit. f. loins. Mik., xv, 3, 1899, p. 338) it may be used for 

 intra-vitam staining of tissues in the same way as methylen 

 blue, by injection or immersion with contact of air. It is 

 especially a granule stain. Similar results ai'e recorded by 

 Aenold {Anat. Anz., xvi, 1899, p. 568, and xxi, 1902, p. 418). 

 See also Ehelich and Lazarus, Anwmie, i, 1898, p. 85 ; Loisel 

 {.Tourn. de I' Anat. et de la Phijsioi., 1898, pp. 197, 210, 217) 

 [intra-vitam staining of sponges) ; and Pbowazek (Zeit. wiss. 

 ZooL, Ixii, 1897, p. 187) (intra-vitam staining of Protozoa). 

 I myself have had very good results with it as an intra- 

 vitam stain. 



According to GrOLOViNK {Zeit. luiss.Mil-., xix, 1902, p. 176), 

 the stain may be fixed in the tissues by means of sublimate, 

 chromic acid, bichromates, picric acid, or platinum chloride, 

 followed by molybdate of ammonium. 



It has also been found useful for staining, in hardened 

 material, the corpuscles of Njssl {q. v.) in nerve-cells. S. 

 Mayke {Lotos, Prague, 1896, No. 2) states that it also stains 

 degenerating myelin. The solutions that have been employed 

 for staining fixed material are strong aqueous ones, 1 per 

 cent, to concentrated. 



310. The Eosins, found in commerce under the names of 

 Eosin, SaflFrosin, Primerose Soluble, Phloxin, Bengal Rose, Ery- 

 throsin, Pyrosin B, Eose B, a I'Eau, etc., are all " acid " 

 phthalein colours. They are not quite identical in their 

 properties. Most of them are soluble both in alcohol and 

 in water, but some only in alcohol {"Primerose a I'Alcuol "). 



They are all diffuse stains, formerly much used as con- 

 trast stains, less so now. Hansen {Anat. Hefte, xxvii, 1905, 

 p. 620) adds 1 drop of acetic acid of 2 per cent, to 9 c.c. of 

 1 per cent, eosin, which makes the stain more selective. 



For Bengal Rose see Geiesbach, Zool. Anz., 1883, p. 172. 



