58 Botanical Microtechnique 



Hematein-Alum (Kornhauser) 



Hematein, an oxidation product oi hematoxylin, is used in the 

 following formula, which is preferred by some workers to the Mayer 

 formula and its modifications. 



0.5 g. hematein. 



Grind in a glass mortar with 10 cc. 95'/^ alcohol. 



Add to 500 cc. potassium aluminum sulphate, saturated aqueous solution. 



The stain is ready to use at once and has good keeping qualities. 



Harris' Hematoxylin 



1 liter 50% alcohol; 1 g. aluminum chloride; 2 g. hematoxylin crystals. 

 Heat on a water bath until dissolved. 

 .\dd 6 g. mercuric oxide; filter. 

 Add 1 "cc. HCl. 



Delafield's Hematoxylin (Slow-Ripening Formula) 

 100 CC. saturated solution of ammonia alum; add drop l)y drop 6 cc. 

 absolute alcohol containing 1 g. hematoxylin. 

 Expose to light in open bottle for 1 week. 

 Filter, and add 2.5 cc. glycerin and 2.5 cc. methyl alcohol. 

 Allow to ripen at least 2 months. Filter as needed. 



Delafield's Hematoxylin (Rapidly-Ripened Formula, Kohl and James) 

 Prepare the (omplete formula as above. Pour into a shallow open dish 

 and expose to a cpiartz mercury-vapor lamp for 2 hr. Another method of 

 ripening (Neild) consists of exposing the liquid to a Cooper-Hewitt light, 

 for 1 hr., 15 cm. from the light, at 140 volts, 3.3 amp. 



The most widely used separate-mordant staining procedure uses 

 the following reagents: 



Iron-Hematoxylin (Heidenhain's), (Iron-Alum Hematoxylin) 

 The niordani consists of a freshly made 4'/c solution c>l iron alum (ferric 

 ammonium sulphate) . Select clean, transparent, violet-colored crystals, 

 especially avoiding crystals with a rusty coating. Discard die solution when a 

 yellow precipitate develops in the bottle. 



Ihc following mordant will keep lor months (Lang) : 



4% iron alum 500 cc. 



Acetic acid (glacial) 5 cc. 



HaSOi (concentrated) 0.0 cc. 



Some satisfactory destaining agents are: 



1. Mordant dihited ^vilh an ecpial xoluiiie ol water. 



2. Saturated aqueous sohition of picric acid. 



3. Equal volumes of mordant :ind liic above picric acid. 



The stock solution of stain is a 0.5% acjtieous solution of hema- 

 toxylin. iVIeasurc the required volinne of distilled water, add a pinch 

 of sodium bicarbonate, about as large as a match head, to a liter of 

 water. Bring the water to the boiling poim. remove from the heater 

 and laid the dye. Do not boil the solution! Cool promptly and store 



