212 



THE AMERICAN MONTHLY 



[November, 



but m^ny plasma cells and bacteria- 

 like forms are. Colonies of mi- 

 crocci are most deeply stained, and 

 the preparations are especially adapt- 

 ed to photography. (I cannot deny 

 the great value of this dye, but can- 

 not consider it so generally useful as 

 carmine. It undoubtedly has advan- 

 tages for certain purposes) . 

 I02. Ehrlich. (a). Uber die speci- 

 fischen Granulationen des 

 Blutes. Verhandlungen d. Berl. 

 Phys. Gesellsch. May i6, 1879. 

 {6). Arch. f. Anat. u. Phys. 1S79. 



Phys. Abth. p. 571-579. 

 (r). Methodologische Beitriige zur 

 Physiologic und Pathologic des 

 verschiedenen Formen der Leu- 

 kocythen. Zeitschr. klin. Med. 

 Berlin. I Heft 3. 

 Ehrlich finds in the anilin dyes a 

 means of distinguishing subordinate 

 groups of similar cells. Each dye 

 brings out clearly the granular con- 

 tents of the cells which are different 

 and characteristic of each type. 

 These ' specific granules ' are clearly 

 shovv^n by taking the blood or paren- 

 chyma of the organ under examina- 

 tion, making a thin layer of it on the 

 cover-glass and drying it in a warm 

 place. The cover will be stained, 

 and in this manner Ehrlich made five 

 distinct typical forms of grains in 

 the blood corpuscles that he called <i, 

 ,5, ^, o, z. Other peculiarities enable 

 these cells to be distinguished. The 

 staining of the granules is a chemical 

 process analogous to the formation of 

 a double salt. The anilins may be 

 divided in two groups difiering chem- 

 ically and histologically, i. Basic 

 anilins made by combining a dye- 

 base and an acid, such as fuchsin, 

 Bismarck brown, safranin and many 

 others. 2. Acid anilins, in which 

 the active dyeing principle is an acid. 

 The granules or *• eosinophilen" (so 

 called because of their aflinity for 

 eosin) stain in all acid anilins, of 

 which Ehrlich has tried thirty. The 

 Y granules or fatty cells, on the con- 

 trary, take the basic dyes. A neu- 

 tral stain ma}' be made by mixing an 



acid and a basic dye together, it will 

 be insoluble in water, but soluble in 

 excess of acid dye. For example, 

 add to a strong solution of methyl- 

 blue a concentrated solution of acid 

 fuchsin which is the soda salt of ros- 

 anilinmonosulfosiiure. To five vol- 

 umes of the last add, with stirirng, i 

 volume methyl blue, and five of water, 

 allow it to settle and filter. Red 

 blood corpuscles stain deeply in this 

 solution, leucocytes show crowded 

 violet granules, the ^-granules ab- 

 sorbent of neutral dyes. These are 

 very small and do not correspond 

 either to the well-known albuminous 

 bodies, or to fat. The «-gi-anules 

 stain in strong glycerin-eosin, in glyc- 

 erin-indulin, and in concentrated 

 watery solution of orftnge. Eosin- 

 indulin-glycerin is most appropriate 

 for the /v-granules. 



103. Curschmann. Ueber das Ver- 



bal ten des Methylgriin zu 

 amyloid-degenerirten Gewe- 

 ben. Arch. path. Anat. und 

 Phys. -Ixxix, 556. 

 Methyl green is recommended as 

 reagent for amyloid substances. It 

 is better than methyl-violet, staining 

 the degenerate tissue violet, the nor- 

 mal green. Sections may be hard- 

 ened in alcohol or chromic acid, and 

 finally put in a i per cent, or, better, 

 a weaker solution of glycerin or 

 levulose. Canada balsam is not ad- 

 missible. Degenerate kidneys give 

 the best results. The hyaline urinary 

 tubules become ultramarine blue, the 

 amyloid substance violet, the normal 

 green. 



The dye that produces these results 

 is made by Meister, Lucius & 

 Browning. Hochst a Main, and is 

 known as green powder M. 



104. Test for Amyloid vSubstance. 



Journ. R. Micr. Soc, 1880, p. 



500. 

 Safranin is recommended for amy- 

 loid substance because it tinges it 

 orange yellow, all the rest red. May- 

 be used in water or alcohol, but 

 not after chromic acid. Acetic 

 acid destroys the difi'erentiation be- 



