Edible anurans have to rely on more than just poison glands which tend to work too late (i.e. after the predator has it in his mouth!) Related articles: How to Rid Your Garden of Toads-tips for dog owners (aside from training the dog of course!)
Manevalâs staining method is a negative staining method. To stain a capsule of a cell by Manevalâs staining method. 1  1 % Congo red solution.  Manevalâs stain.
For this reason we use a NEGATIVE STAIN to visualize them. That is, we use a stain which stains the background against which the uncolored capsule can be seen. Our procedure, the Gin's Method, uses india ink to color the background and crystal violet to stain the bacterial cell body.