60 



Biological Stains 



420 440 460 480 500 520 540 560 580 600 620 640 660 680 700 



Wave Lengths in Millimicrons 



Fig. 5. Absorption curve of malachite green. 



a principal band in the orange and a secondary band in the violet. 

 Both the absorption curve and the color of the dye could be 

 matched closely by mixing a suitable blue and a yellow dye in the 

 correct proportions. All green dyes absorb appreciable amounts 

 of violet light as well as of red light. 



