720 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [38] 
beds can be explaimed. From 1800 to 1815 there were taken yearly from 
the beds of Cancale less than two million oysters. The oysters, both 
marketable and spawning, had thus an opportunity to accumulate in 
greater quantity to form the increased production which occurred in 
1822. If the French oysters live as long as those of the Schleswig- 
Holstein beds, some of this stock, which had accumulated during the 
period of comparative rest at the time of the Napoleonic wars, would have 
been lying upon the banks as late as about 1830. From this time on for 
nearly a score of years it is probable that the ever-increasing yield was 
the produce of only those oysters existing upon the beds from 1820 to 
1830. Krom 1840 to 1847 the number of oysters taken was extraordi- 
narily great—evidently too great for the productiveness of the beds, since 
from this time they produced fewer oysters each year. 
The total number of oysters taken between the years: 1840 and 1847 
was about 512,000,000, being on an average about 64,000,000 per year. 
If this average represents the natural stock of marketable, full-grown 
oysters upon the beds of Cancale, then the number taken yearly should 
not have been over twenty-six to twenty-seven millions, if it was desired 
that this degree of productiveness should be maintained. This I assert 
upon the supposition that the productiveness of the oysters in the Bay 
of Cancale is no greater than upon the Schleswig-Holstein banks. If 
this productiveness was higher than upon our sea-flats, then we ought 
to have at Cancale, not 421 half-grown oysters for every 1,000 full-grown 
ones, but, for example, 500. Under these cireumstances the presence of 
64,000,000 matured oysters would permit the fishing of 32,000,000 yearly, 
but no more if the fruitfulness of the beds would be kept at that number, 
since such a stock would be absolutely necessary in order that a suffi- 
cient number of young should be produced to secure the maturing of 
32,000,000 yearly. 
After the impoverishment of the beds of Cancale the inspection officers 
enforced once more the laws protecting the oyster, since they did not 
believe that all the mature breeding oysters had been taken off the beds. 
Upon some of these beds there has already been a very significant in- 
crease of oysters through this action; for in 1872~73, 7,300,000 oysters 
were taken, in 1873~74, 9,056,000, and in 1874~75, 9,342,000. To pre- 
serve oyster-beds a stock of full-grown oysters, for the purposes of prop- 
agation, must be left lying upon the banks. The number thus left must 
depend upon the fruitfulness of the oysters of each section, or, still bet- 
ter, of each single bed. Accordin g to the experience of oystermen, the 
most fruitful as well as the largest of the Schleswig-Holstein oyster- 
beds is the Huntje Bank. The proportion of medium oysters upon this 
bed is 484 per thousand, which is thus greater than the mean produc- 
tiveness of the whole Schleswig-Holstein oyster-beds. The productive- 
ness of smaller beds is belowthe average of 421 per thousand. As ex- 
amples, we give the proportions of the following beds: Steenack, 385 per 
thousand; Hédrnum, 319 per thousand; West Amrum, 165 per thousand. 
