192 ANURA CHAP. 



during the winter in a glass with water-cress. While the temper- 

 ature was near freezing the frog sat in the water, very lethargic, 

 breathing perhaps once every quarter of an hour. Its colour 

 was light green. When the water-cress was cut and removed, 

 the frog darkened and became at last quite a discoloured grey. 

 When the water-cress was put back, the creature reassumed the 

 light yellowish-green colour, remaining in its lethargic condition 

 until it became lively in the spring sunshine. 



The European tree-frog spends most of its time in the summer, 

 after the pairing is over, in trees, often in the very crowns ; but 

 the neighbourhood of even a small patch of Indian corn has still 

 greater attractions. There are all sorts of green insects to be 

 caught, there are fair chances of coming across the common 

 Cabbage White, a butterfly which the tree-frog loves, and last 

 not least the large luscious leaves afford a firm foothold, and the 

 axillae between stalk and broad-based leaves are just the places 

 for the frog to slip into, where nobody can find it. During the 

 day they mostly sit still, on the keen look-out for passing insects, 

 which, when they settle within reach, are jumped at ; otherwise 

 they have first to be stalked. The jump is quite fearless, 

 regardless of the height above ground; there is the leaf upon 

 which the prey sits, and even if this leaf be missed, there are 

 others, and one of them is sure to be struck by some -of the discs 

 of either fingefs or toes. If the fall is broken by the toes, .and 

 the new leaf or branch is very elastic and bends down, then there 

 are some frantic antics to be gone through until the frog has 

 settled itself again. Then the large blue-bottle, or the butterfly, 

 is devoured at leisure, wings and all being poked in with the 

 assistance of the little hands. But the real hunting-time is the 

 night. 



During a shower the frog shifts its position to the under side 

 of the leaf, or into a less slippery position, and during continuous 

 wet it descends into the grass, or it takes to the water. Its 

 greatest enemy is the Grass Snake, which prefers it to anything 

 else, not minding the poisonous secretion of the skin, which is 

 sharp enough to produce sneezing or even temporary blindness 

 when incautiously brought into the human eye. 



The male has an internal vocal sac, which, when inflated, 

 bulges out the whole throat into a globe, much larger than the 

 head. The voice is a sharp and rapidly -repeated note, something 



