To the fish in the detached tanks and pools when the heat, by exhausting the water, deprives them at once of motion and sustenance, the practical effect must be the same as when the frost of a northern winter encases them in ice. Nor is it difficult to believe that they can successfully undergo the one crisis when we know beyond question that they may survive the other.[1] [Footnote 1: YARRELL, vol. i. p. 364, quotes the authority of Dr. J. Hunter in his _Animal OEconomy_, that fish, "after being frozen still retain so much of life as when thawed to resume their vital actions;" and in the same volume (_Introd._ vol. i. p. xvii.) he relates from JESSE'S _Gleanings in Natural History_, the story of a gold fish (_Cyprinus auratus_) which, together with the water in a marble basin, was frozen into one solid lump of ice, yet, on the water being thawed, the fish became as lively as usual Dr. RICHARDSON, in the third vol. of his _Fauna Borealis Americana_, says the grey sucking carp found in the fur countries of North America, may be frozen and thawed again without being killed in the process.] _Hot-water Fishes_.--Another incident is striking in connection with the fresh-water fishes of Ceylon. I have mentioned elsewhere the hot springs of Kannea, in the vicinity of Trincomalie, the water in which flows at a temperature varying at different seasons from 85° to 115°. In the stream formed by these wells M. Reynaud found and forwarded to Cuvier two fishes which he took from the water at a time when his thermometer indicated a temperature of 37° Reaumur, equal to 115° of Fahrenheit. The one was an Apogon, the other an Ambassis, and to each, from the heat of its habitat, he assigned the specific name of "Thermalis."[1] [Footnote 1: CUV. and VAL., vol. iii. p. 363. In addition to the two fishes above named, a loche _Cobitis thermalis_, and a carp, _Nuria thermoicos_, were found in the hot-springs of Kannea at a heat 40° Cent., 114° Fahr., and a roach, _Leuciscus thermalis_, when the thermometer indicated 50° Cent., 122° Fahr.--_Ib_. xviii. p. 59, xvi. p. 182, xvii. p. 94. Fish have been taken from a hot spring at Pooree when the thermometer stood at 112° Fahr., and as they belonged to a carnivorous genus, they must have found prey living in the same high temperature.--_Journ. Asiatic Soc. Beng_. vol. vi. p. 465. Fishes have been observed in a hot spring at Manilla which raises the thermometer to 187°, and in another in Barbary, the usual temperature of which is 172°; and Humboidt and Bonpland, when travelling in South America, saw fishes thrown up alive from a volcano, in water that raised the temperature to 210°, being two degrees below the boiling point. PATTERSON'S _Zoology_. Pt. ii p. 211; YARRELL'S _History of British Fishes_, vol. i. In. p. xvi.] _List of Ceylon Fishes._ I. OSSEOUS. Acanthopterygii.