370 THE ZOOLOGIST. 



pond ready for use. The store pond is generally floored with 

 tarred planks, an expensive material, but found to be better than 

 either the natural ground, which becomes foul, or than brick, 

 which is too cold. The water is kept about 4 ft. in depth. 



Austrian Oyster Culture is interesting as presenting a 

 combination and evolution of the preceding systems. The 

 Austrian Society for Fisheries and Sea Fishing appears to have 

 begun Oyster culture more or less on French or Dutch lines, but 

 to be now adopting mostly the Italian system. In 1889 the 

 society established a farm at Zaule, near Trieste. At some 

 120 yards from the shore, an area of 100 square yards was 

 enclosed by stake work, 20 yards long by 5 yards wide, with a 

 depth of 4 yards at mean tide. Above high-water mark the stakes 

 were united by cross bars with supporting piles at intervals of 

 2j yards. These stakes were also 2j yards out of water at low 

 tide, and were driven 4 to 5 yards into the thick muddy bottom. 

 From the cross bars were hung frames of galvanized wire netting, 

 2 by 3 yards, intertwined with branches for the double purpose 

 of collecting spat, and preventing it from being carried out of the 

 enclosed space by any seaward current. Within this space were 

 placed collectors of every kind, and between them Oyster-mothers 

 were placed in cages of wide-meshed wire netting, so fixed that 

 they hung 1 J yards under water. During the months of January 

 and March the first young Oysters were detached from the col- 

 lectors to the number of 40,000, and, placed in breeding safes, 

 suspended from the palisade in about 2 yards of water. After 

 this trial the society enlarged the enclosure to 400 square yards, 

 half of which was to serve as a breeding, and half as a rearing, 

 ground. But in the spring of 1892 the erection of a petroleum 

 factory so polluted the water that the undertaking had to be 

 abandoned. 



The society then initiated experiments at Palazza, where 

 shallows of 30,000 square yards, with rather less than one yard 

 depth at low water, were used. The bottom is hard shelly sand. 

 In 1891, 5000 lime-coated tiles were laid in heaps as collectors. 

 In 1892, 100,000 young Oysters were detached, and placed to 

 grow in galvanized wire safes. These were suspended from ropes 

 attached to stakes, and hung 1J yards under water at low tide. 

 Both stakes and ropes were in the Moreri channel, which is about 



