_Law of Battle._—Almost all male birds are extremely pugnacious, using their beaks, wings, and legs for fighting together. We see this every spring with our robins and sparrows. The smallest of all birds, namely the humming-bird, is one of the most quarrelsome. Mr. Gosse[61] describes a battle, in which a pair of humming-birds seized hold of each other’s beaks, and whirled round and round, till they almost fell to the ground; and M. Montes de Oca, in speaking of another genus, says that two males rarely meet without a fierce aerial encounter: when kept in cages “their fighting has mostly ended in the splitting of the tongue of one of the two, which then surely dies from being unable to feed.”[62] With Waders, the males of the common water-hen (_Gallinula chloropus_) “when pairing, fight violently for the females: they stand nearly upright in the water and strike with their feet.” Two were seen to be thus engaged for half an hour, until one got hold of the head of the other which would have been killed, had not the observer interfered; the female all the time looking on as a quiet spectator.[63] The males of an allied bird (_Gallicrex cristatus_), as Mr. Blyth informs me, are one third larger than the females, and are so pugnacious during the breeding-season, that they are kept by the natives of Eastern Bengal for the sake of fighting. Various other birds are kept in India for the same purpose, for instance the Bulbuls (_Pycnonotus hæmorrhous_) which “fight with great spirit.”[64]