THE OCEAN WORLD. 
3Di 
estuary of the Thames and Medway, is most efficient. The oysters 
reared in them, called “ natives,” in contradistinction to those called 
commons.” which are bred in their natural beds, are justly considered 
to be very superior in flavour, although they are a mixed breed, being 
brought from every quarter to augment the stock. 
The Thames, or “ native ” system, is as follows : Every year each 
layer is gone over and examined by means of a dredge, successive 
portions being done day by day, till it may be said that each individual 
oyster has been examined ; the young brood is detached from its bed* 
the double oysters are separated, and all kinds of enemies killed- 
During three days in each week dredging is pursued for “ planting > 
that is, for transference from one bed to another more suitable i° r 
their growth or fattening, and for the removal of the dead or sickly 
oysters and mussels. On the other three days dredging for market 
takes place, when the more mature beds are dredged, and as many 
are lifted as are required. Not only is this constant dredging °*' 
the beds themselves necessary, but the public beds immediately 
outside require the same care to keep them in a fit state, and fr ee 
from enemies. 
The same story of over-iishing and improvidence extends round our 
whole coast. The far-famed Pandores obtained at Preston Pans, neat 
Edinburgh, once so cheap, are becoming scarce and dear. The broo 
is caught and barreled for export .to Holland and other pla ceS ’ 
especially the Thames oyster farms. English buyers pick the gro^n 
oysters for Manchester and other large provincial markets, and the 
Corporation of Edinburgh, the Duke of Buccleuch, and other p r °' 
prietors of the foreshore, have just interfered in time to prevent the 
total destruction of the trade, when the wild song of the Cockenz 16 
dredgerman might have been left to charm some future antiquary, 06 
it is now said to charm the oyster into the dredge with its refrain : 
The herring it loves the merry moonlight, 
The mackerel it loves the wind ; 
But ihe oyster it loves the dredger's song, 
For it comes of a gentle kind.” 
The Scallop-shell (Pecten) is round, nearly equal-sided, resting 011 
the right valve, which is more convex, and marked with radiating 11 ^ 
Linnaeus made the mistake of confounding with the Ostrea a g re 
number of shells, which, by their channeled edges and surface , 
