269 
Nores on OrGANic SrRucTURE as ILLUSTRATED by means of 
Dyes. By Watrer Assry, M.R.C.S. 
Turis Journal has of late presented to its readers a remark- 
able series of papers by Dr. Lionel Beale, embodying the 
results obtained from the investigation of organic structures 
into a doctrine that is likely to give the coup de grace to the 
already staggering cell-theory of Schwann. 
Dr. Beale, having conceived the happy idea of staining the 
tissues with carmine, found that a permanent stain was 
acquired by certain portions only of the tissue, including all 
those which are generally supposed not to have reached their 
ultimate grade of development, and excluding those which 
have evidently undergone a structural process. 
This new and conspicuous fact suggested the division of 
all organized matter into the two easily determined sections 
of “germinal matter” and “formed matter,” the former 
being dyed, the latter unaffected, by carmine. The “ germinal 
matter”? is well represented by the nucleus and nucleolus ; 
the “formed matter,” by the cell-wall and spiral fibre. 
Dr. Beale also inferred, from the presence of gradated 
colour in the stained “germinal matter,” that it lost its pro- 
clivity for the dye in the course of its gradual transition into 
the ‘‘ formed matter.” 
It is very obvious that this selective staining power of 
carmine is of great value to the physiologist, and that still 
further advantage would be derived from the possession of 
one or more dyes capable of staining the whole or part of 
that which is not coloured by the carmine; also, that the one 
colour ought sufficiently to contrast with the other. 
Iodine has long and deservedly been in use and repute ; 
but, apart from its value as a test for starch and cellulose, it 
does not avail much as a dye, the cell and the cell-contents 
usually differing only in the intensity of the uniform and 
fugitive brownish-yellow conferred upon them. 
Substances largely possessed of the desired properties are, 
however, easy to obtain, and easy to use. They are most 
abundant among the compounds of aniline. 
Magenta, one of the most brilliant of these, has already 
been used by the microscopist, but its distinctive qualities 
seem to have escaped suspicion. This dye, like most of its 
congeners, has selective staining power as great as that of 
carmine, and still more limited, Altogether unattracted by 
