114 



ANATOMY 



brain tissues, as it causes a pronounced distention of the nuclei and 

 gives a poor preservation of the nuclear contents. 



The more important data are given in tables 73, 74, 75, 76, 77. 



TABLE 77 



The percentage of solids in brains of rats of various ages kept from four to eighteen 

 weeks in solutions of 4 per cent formaldehyde (computations made from original 

 brain weights) 



Swelling reactions. To determine whether slight changes in 

 the composition of the brain could be detected by a swelling 

 reaction, Plant ('19) tested the effect of Miiller's fluid (contain- 

 ing 2.5 per cent potassium bichromate plus one per cent sodium 

 sulphate). A brain immersed in this solution not only hardens, 



