. [23] OYSTER CULTIVATION IN THE NETHERLANDS. 1023 
As this animal is found in all these different localities, it will not 
astonish us that it occasionally occurs on the coast of the Netherlands, 
and, in fact, it is rather surprising that this animal is so rare in our coast 
fauna. We shall find an explanation of this circumstance by examin- 
ing the nature of the bottom; the Murex erinaceus does not live ona 
sandy or clay bottom, but shows a decided preference for rocky bot- 
toms. That our oyster grounds have so far been free from this animal, 
which is so hurtful to the oyster, must in the first place be ascribed to 
the bottom, and in the second place to their shallowness. We are all 
the more inclined to embrace this opinion when we remember that the 
Zeeuw oyster grounds for more than a century (Job Baster) have 
been stocked not only with oysters imported from Arcachon (as the 
oyster cultivators at Brwinisse assured me they have worked with Arca- 
chon oysters for several years), but also with young oysters from Great 
Britain, and that the “ Drill” could easily have been introduced from the 
last-mentioned country. The scattered cases where the Murex referred 
to have been observed on the coast of the Netherlands may possibly have 
been caused by its having been introduced with other shell fish; if 
this could be ascertained beyond a doubt, we would possess a proof (al- 
though only a negative one) of the correctness of our supposition that 
the non-occurrence or rare occurrence of the “ Drill” must principally be 
ascribed to conditions existing on our oyster-grounds which are not 
favorable to the development of this animal. 
If we are to have a more thorough examination of the oysters im- 
ported from Arcachon (and other points on the coasts of France and 
Great Britain), and planted on the Zeeuw oyster grounds, with the 
view to ascertain whether or not the “Drill” is found there, we deem it 
necessary to answer the following question: “Must the Murex erinaceus 
L., even now be considered as a representative—though a very scarce 
one at that—of the fauna of the Eastern Scheldt and the neighboring 
waters ?” Both for this investigation and for an accurate determination 
of the localities where natural oyster and muscle grounds are found, an 
exhaustive examination, from a zoological point of view, of the East- 
ern Scheldt seems absolutely necessary. The matter of undertaking 
such an investigation will form the subject of serious consideration by 
the commission. 
Very respectfully, 
Dr. P. Pi€; HORK, 
Secretary of the Commission of the Zoological Station.” 
The above appendix will, in the opinion of the commission, give an 
idea of the present condition of the investigation. In said appendix it 
‘has been mentioned repeatedly that in our final report, which will be 
published when the entire investigation has been brought to a close, 
all the results will be given in full, if necessary, accompanied by illus- 
trations and maps. ' 
