1895 THE MICROSCOPE. 175 



SCIENCE-GOSSIP. 



Haemalum and Haemacalcium Staining Solution. — Dr. 

 Paul Mayer recommends the use of two staining solutions made 

 from hsematein, the essential staining constituent of logwood. 

 When pure, ha3matein is a brown red pow^der, and crystallizes 

 with one or three equivalents of water. It is most frequeatly 

 found in commerce as haemaieinum crystallizatum, a compound 

 of ha^matein and about 9 percent, of ammonia, and is more 

 properly designated ammonia-ha:^matein. When pure, li^ematein 

 and its ammoaia compounds should not only be perfectly solu- 

 ble in distilled water and alcohol, but should remain so on addi- 

 tion of acetic acid. From hsematim is prepared a soUition 

 called for short, haemalum. 



One gram of the pigment is dissolved by aid of heat in 50 ccm. 

 of 90 per cent alcohol and then added to a solution of 50 grm. 

 of alum in 1 litre of distilled water. W^hen cold it may be nec- 

 essary to filter, but if the constituents have been pure this is 

 quite superfluous. The solution is ready for use at once. It 

 may be necessary to add a thymol crystal, in order to prevent 

 the formation of fungi. 



For staining sections h?ematin is used like Boshmer's ha?ma- 

 toxylus, and if required the preparations may afterwards be 

 w^ashed with, ordinary water, distilled water or 1 per cent alum 

 solution. 



Haemacalcium, which is proposed as a substitute for Kleinen- 

 berg's ha^matoxylin, is made with the following ingredients: 

 Hffimatein, or ammonia hsematein, 1 gram ; aluminium chloride, 

 1 gram ; calcium chloride, 50 grams ; acetic acid, 10 ccms ; 70 

 per cent alcohol, 600 ccms. 



The first two substances are rubbed together very intimately ; 

 the acetic acid and alcohol are then to be added, with or with- 

 out the aid of heat. Last of all, the calcium chloride is added. 

 The fluid is of a red violet hue. After having been washed in 

 neutral 70 per cent alcohol, the preparations are violet or blue, 

 and rarely require to be treated with acidulated alcohol. If too 

 red they may be treated with 2 per cent aluminium chloride 

 dissolved in acohol. — Journal Royal Mic. Soc, Mittheil. Zool. Stat, 

 zu Neapel. 



