AQUAAIUH. 



conunon carp, except that its cheeks and gill-covers are of a 

 brilliant orange hue, and its fins inchned to orange-red. It is 

 rather local, but may be found in many ponds in the neighbour- 

 hood of London. The usual weight of the Prussian carp is 

 about half a pound. 



The Tench is a fish well fitted 

 to be a tenant of . the aquarium. 

 Though common enough in kept 

 and ornamental waters, it is but 

 sparingly found in pools and 

 rivers. Its usual length is 

 about ten inches, and its gene- 

 ral colour greenish brown or 

 THE TENCH. oUve, having a golden hue, which 



latter tint is most conspicuous 

 on the under parts of the fish. It may be easily known from 

 the carp by the comparative smaUness of its scales and froin 

 being more slender. It is peculiarly adapted to the narrow 

 limits of the aquarium, where the quantity of oxygen is never 

 over plentiful ; for from experiments that have been made it is 

 proved that the tench is able to breathe when the quantity of 

 oxygen is reduced to a five-thousandth part of the bulk of the 

 water. The quantity of oxygen present in ordinary river water 

 is one in the hundred. Indeed, from its tenacity of life, the 

 tench might claim relationship with the caf-fish. " A piece of 

 water," says Mr. TarreU, " which had been ordered to be filled 

 up, and into which wood and rubbish had been thrown for 

 years, was ordered to be cleared out. Persons were accord- 

 ingly employed ; and, almost choked up by weeds and mud, so 

 little water remained that no person expected to see any fish, 

 excepting a few eels, yet nearly two hundred brace of tench of 

 all sizes, and as many perch, were found. After the pond was 

 thought to be quite free, under some roots there seemed to be 

 an animal which was conjectured to be an otter ; the place was 

 surrounded, and on opening an entrance among the roots, s^ 

 tench was found of most singular form, having literally assumed 

 the shape of the hole in which he had of course for many years 

 been confined. His length firom eye to fork was thirty-three 

 inches ; his circumference almost to the tail was twenty-seven 

 inches; his weight eleven pounds nine ounces and a quarter- 

 the colour was also singular, his belly being that of the char or 

 vermilion. This extraordinary fish, after having been inspected 

 by many gentlemen, was carefully put into a pond, and at the 



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