220 THE HISTOET OF ANIMALS. [B. VIII 



by the dragon-serpent. In the ballerus and tilon a worm is 

 produced, under the influence of the dog-star, which makes 

 them rise to the surface and become weak, and when they 

 come to the surface they are killed by the heat; a violent dis- 

 ease attacks the chalcis, which is destroyed by a number of 

 lice, which are produced under its gills ; no other fish appear 

 to be subject to such a disease. 



13. Fishes are poisoned with the plant called mullein, for 

 which reason some persons capture them by poisoning the 

 waters of rivers and ponds; and the' Phoenicians poison the 

 sea in the same way. There are two other plans which are 

 adopted for the capture of fish ; for since fish avoid the deep 

 parts of rivers in cold weather (for even otherwise the river 

 water is cold), they dig a ditch through the land to the river, 

 which they cover over with grass and stones so as to resemble 

 a cave, with one opening from the river, and when the frost 

 comes on they capture the fish with a basket. The other mode 

 of fishing is practised both in summer and winter. In the 

 middle of the stream they raise a structure with faggots and 

 stones, leaving one part open for a mouth ; in this a basket 

 is placed, with which they catch the fish, as they take away 

 the stones. 



14. Rainy years agree with all the testacea except the pur- 

 pura ; this is a proof of it, if placed near the mouth of a 

 river, they take the fresh water, and die the same day. The 

 purpura will live about fifty clays after it has been taken. 

 They are nourished by each other, for a plant like a fucus 

 or moss grows upon their shells. They say that whatever is 

 cast to them for food is done for the sake of weight, that 

 they may weigh the more. 



15. Dry weather is injurious to other testacea, for it 

 renders them fewer in quantity and inferior in quality, and the 

 pectens become more red. In the Pyrrha?an Euripus the pec- 

 tens perish, not only from the instrument with which the 

 fishermen scrape them together, but also from dry weather. 

 The other testacea thrive in wet weather, because it makes 

 the sea- water fresher. The cold of the Pontus and of the 

 rivers that flow into it renders bivalve shells rare. The uni- 

 valves, however, are frozen in cold weather. This is the 

 nature of aquatic animals. 



