156 ANURA CHAP. 



species for the hills, and that of the other for the plains, is well 

 marked. 



While B. igneus prefers standing waters with plenty of 

 vegetation, B. pacliypus is often found in the smallest occasional 

 puddles produced by recent rain, for instance in the ruts of 

 roads. Both species have otherwise much in common. They are 

 essentially aquatic. They hang in the water, with their legs 

 extended, nose and eyes just above the surface, and bask or lie in 

 wait for passing insects, the fire-bellied kind preferring to con- 

 ceal itself in the vegetation of the margins of ponds. During 

 the pairing season, in Germany in the month of May, they are 

 very lively and perform peculiar concerts, one male beginning with 

 a slowly repeated note like " hoonk, hoonk," or " ooh, ooh," in which 

 all the other males soon join, so that, when there are many, an 

 almost continuous music is produced. This sound is not at all 

 loud, a little mournful and very deceptive. It appears to be a 

 long way off, certainly at the other end of the pond, until by 

 careful watching you see the little creature almost at your very 

 feet. But on the slightest disturbance the performance ceases, 

 they dive below and hide at the bottom. The yellow-bellied 

 kind, when surprised in a shallow puddle, skims over the mud, 

 disturbs it, and allows it to settle upon its flat body, so that 

 nothing but the little glittering eyes will betray its concealment. 

 When these toads are surprised on land, or roughly touched, they 

 assume a most peculiar attitude, as shown in Fig. 31. The 

 head is partly thrown back, the limbs are turned upwards 

 with their under surfaces outwards, and the whole body is 

 curved up so that as much as possible of the bright yellow 

 or red markings of the under parts is exposed to view. The 

 creature remains in this strained position until all danger seems 

 passed. In reality this is an exhibition of warning colours, to 

 show the enemy what a dangerous animal he would have to deal 

 with. The secretion of the skin is very poisonous, and the 

 fire- toads are thereby well protected. I know of no creature 

 which will eat or even harm them. I have kept numbers in a 

 large vivarium, together with various snakes, water-tortoises, and 

 crocodiles, but for years the little fire-bellies remained unmolested, 

 although they shared a pond in which no other frog or newt could 

 live without being eaten. Hungry water-tortoises stalk them 

 under water, touch the intended prey with the nose in order to 



