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.
The cells that decolorize easily are gram negative, those that hold the primary stain are gram positive. Negative staining is used to show better morphology(shape) and size of cells, as well as being used in hard to stain bacteria such as coccobacilli.