In Siam the fighting-fish (Betta pugnax) is widely noted. The following account of this fish is given by Cantor:[11]
"When the fish is in a state of quiet, its dull colors present nothing remarkable; but if two be brought together, or if one sees its own image in a looking-glass, the little creature becomes suddenly excited, the raised fins and the whole body shine with metallic colors of dazzling beauty, while the projected gill membrane, waving like a black frill round the throat, adds something of grotesqueness to the general appearance. In this state it makes repeated darts at its real or reflected antagonist. But both, when taken out of each other's sight, instantly become quiet. The fishes were kept in glasses of water, fed with larvæ of mosquitoes, and had thus lived for many months. The Siamese are as infatuated with the combats of these fish as the Malays are with their cock-fights, and stake on the issue considerable sums, and sometimes their own persons and families. The license to exhibit fish-fights is farmed, and brings a considerable annual revenue to the king of Siam. The species abounds in the rivulets at the foot of the hills of Penang. The inhabitants name it 'Pla-kat,' or the 'fighting-fish'; but the kind kept especially for fighting is an artificial variety cultivated for the purpose."
A related species is the equally famous tree-climber of India (Anabas scandens). In 1797 Lieutenant Daldorf describes his capture of an Anabas, five feet above the water, on the bark of a palm-tree. In the effort to do this, the fish held on to the bark by its preopercular spines, bent its tail, inserted its anal spines, then pushing forward, repeated the operation.
Fear and Anger in Fishes.—From an interesting paper by Surgeon Francis Day[12] on Fear and Anger in Fishes we may make the following extracts, slightly condensed and with a few slight corrections in nomenclature. The paper is written in amplification of another by Rev. S. J. Whitmee, describing the behavior of aquarium fishes in Samoa.
Fig. 125.—Squaw-fish, Ptychocheilus grandis Agassiz. Running up a stream to spawn, the high water, after a rain, falling, leaves the fishes stranded. Kelsey Creek, Clear Lake, California, April 29, 1899. (Photograph by O. E. Meddaugh.)—Page 164.
The means of expression in animals adverted to by Mr. Darwin (excluding those of the ears, which would be out of place in fishes) are: sounds, vocally or otherwise produced; the erection of dermal appendages under the influence of anger or terror, which last would be analogous to the erection of scales and fin-rays among fishes. Regarding special expressions, as those of joy, pain, astonishment, etc., we could hardly expect such so well marked in fishes as in some of the higher animals, in which the play of the features often affords us an insight into their internal emotions. Eyes[13] destitute of movable eyelids, cheeks covered with scales, or the head enveloped in dermal plates, can scarcely mantle into a smile or expand into a broad grin. We possess, however, one very distinct expression in fishes which is absent or but slightly developed in most of the higher animals, namely, change of color. All are aware that when a fish sickens, its brilliant colors fade, but less so how its color may be augmented by anger, and a loss of it be occasioned by depression, the result of being vanquished by a foe. Some forms also emit sounds when actuated by terror, and perhaps in times of anger; but of this last I possess no decided proofs.
Similar to the expression of anger in Betta is that of the three-spined stickleback (Gasterosteus aculeatus).[14] After a fight between two examples, according to Couch, "a strange alteration takes place almost immediately in the defeated party: his gallant bearing forsakes him; his gay colors fade away; he becomes again speckled and ugly; and he hides his disgrace amongst his peaceable companions who occupy together that part of the tub which their tyrants have not taken possession of; he is, moreover, for some time the constant object of his conqueror's persecution."