FISH OUT OF WATER 305 



water, of materials naturally found at the bottom ; but 

 Doras, I believe, is the only one that builds them on the 

 beach, of materials sought for on the dry land. 



Such amphibious habits on the part of certain tropical 

 fish are easy enough to explain by the fashionable clue of 

 ' adaptation to environment.' Ponds are always very 

 likely to dry up, and so the animals that frequent ponds 

 are usually capable of bearing a very long deprivation 

 of water. Indeed, our evolutionists generally hold that 

 land animals have in every case sprung from pond animals 

 which have gradually adapted themselves to do without 

 water altogether. Life, according to this theory, began in 

 the ocean, spread up the estuaries into the greater rivers, 

 thence extended to the brooks and lakes, and finally 

 migrated to the ponds, puddles, swamps and marshes, 

 whence it took at last, by tentative degrees, to the solid 

 shore, the plains, and the mountains. Certainly the 

 tenacity of life shown by pond animals is very remarkable. 

 Our own English carp bury themselves deeply in the mud 

 in winter, and there remain in a dormant condition many 

 months entirely without food. During this long hibernat- 

 ing period, they can be preserved alive for a considerable 

 time out of water, especially if their gills are, from time 

 to time, slightly moistened. They may then be sent to 

 any address by parcels post, packed in wet moss, without 

 serious damage to their constitution ; though, according 

 to Dr. Giinther, these dissipated products of civilisation 

 prefer to have a piece of bread steeped in brandy put intc 

 their mouths to sustain them beforehand. In Holland, 

 where the carp are not so sophisticated, they are often 

 kept the whole winter through, hung up in a net to keep 

 them from freezing. At first they require to be slightly 

 wetted from time to time, just to acclimatise them gradu- 

 ally to so dry an existence ; but after a while they adapt 



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