CULTIVATION OF OYSTERS BY NATURAL AND ARTIFICIAL METHODS. 9 



vate company. I premise by stating that commons are absolutely necessary 

 for the stocking of private beds ; they are generally in the neighbourhood of 

 private beds, and the spat which falls upon them is the produce of the oysters 

 upon the private bed. These commons are worked by poor men to obtain 

 what they can upon them, and sell them to the owners of the beds ; in so 

 doing they keep the ground clean for the reception of spat. 



In the case of the Roach River Fishery, the commons are situated in a 

 comparatively narrow river, and the commons adjoin the private beds almost 

 as near as the various paving stones in the streets. The spat, therefore, which 

 are born on paving-stone A (which is private) are very likely to fall on 

 the neighbouring paving-stone B (which is " commons ") ; anyhow the spat is 

 carried up and down by the tide, and must of necessity fall in the river. 

 The dredgermen perpetually work these commons, and in so doing keep them 

 ready for the reception of spat. When the spat falls, they pick it up in the 

 form of brood, and sell it to the oyster-proprietors, from whose oysters it ori- 

 ginally came. Now it would not be right that oysters belonging to Mr. A 

 should become the property of Mr. B, because they happen to swim over an 

 imaginary hue and settle on the adjoining ground ; it would be just the same 

 thing as if, a farmer breeding a number of lambs in a private field, these lambs, 

 because they happen to get over into a common where donkeys and geese are 

 feeding, should become the property of the gipsies. 



The case of the Heme Bay Fishery is different from that of the Roach River. 

 Here, as will be seen from the map, the oysters may come from anywhere. 

 The Whitstable people said they came from their ground ; a few of them 

 might possibly have done so, but experience shows that the set of the tides 

 is towards the flats out to sea, and there oysters are always found. The 

 authorities who laid down the Admiralty Charts gave their evidence before 

 the House of Commons, that the set of the tide at Heme Bay was from east 

 to west ; in fact their evidence was hardly needed, as the drift of the shingle 

 along the shores of Heme Bay amply proves it. Whitstable being to the 

 westward of Heme Bay, the prevailing set of the tide would carry the spat 

 back to their ground, and not on to that of the Heme Bay ground. There 

 was not very long ago a large number of spat picked up on the Heme Bay 

 ground, and I learnt from observant persons living at Heme Bay that at that 

 time the wind was from the eastward. 



Periwinkles. — To those who lay oysters on the foreshore I would now ven- 

 ture to give a valuable hint, which they may possibly know before. Between 

 high- and low-water mark green weed is very apt to accumidate ; this col- 

 lects mud, and in other respects docs injury to the oysters. "No amount of 

 dredging or other cleaning will keep this green weed off; it is nevertheless 

 very desirable to get rid of it ; and this would form an excellent problem for 

 those who are in the habit of studying what is called the police of nature — 

 that is, to mark the way in which the undue increase of one animal is kept 

 down by the increase of another. Everybody knows that periwinkles are 

 of great use in keeping clean the walls of an aquarium. My friends Mr. 

 Wiseman and Mr. Browning of Paglesham, who are proprietors of large 

 oyster-fisheries, have applied the observed fact of periwinkles eating weeds 

 to a practical operation on a large scale. 



The foreshore where their oysters are laid is very subject to this green 

 weed ; they have therefore turned out large numbers of periwinkles upon it, 

 and these, eating up the green weed, clean the foreshore in the most wonder- 

 ful way. It is curious to remark how periwinkles, obeying their apparently 

 natural instinct, are in the habit of climbing up poles which are put in as 



