The perfect frog, after transformation, is smaller than the larva.
The importance of the osmotic pressure of sea-water in biology will be easily understood from the fact that a frog placed in sea-water loses water by exosmosis and soon becomes 20% lighter than its original weight, while a true salt-water fish suddenly transferred to fresh water gains water by endosmosis, swells up and quickly succumbs.
CUCKOO-SPIT, a frothy secretion found upon plants, and produced by the immature nymphal stage of various plant-lice of the familiar Cercopidae and Jassidae, belonging to the homopterous division of the Hemiptera, which in the adult condition are sometimes called frog-hoppers.
A remarkable flying-frog was discovered by Professor A.
Ranarum is found in the alimentary canal of the frog and growing on its excrement.