Change of Colour in Frogs

Abstract

AT the commencement of “the rains” (say, beginning of June), in the island of Bombay, after the first showers, when a little water lodges in the depressions of the old-quarry tanks, the frogs issue from the crevices of the trap-rock to spawn, when the ma'es (some of which are 18 inches in length from tip of toe to end of digit) assume a bright mustard-yellow colour, while the females remain brown as usual; and this change of colour takes place so rapidly, and the frogs are so numerous, that, with the falling of the showers, the bottom of the quarry becomes suddenly yellow. I never saw a frog so coloured at any other time, and I witnessed the fact above mentioned for at least two successive seasons in the same old quarry.