[5] OYSTER CULTIVATION IN THE NETHERLANDS. 1033 
especially in Germany and England, is so unlimited, that even in the 
most favorable years a good price can be obtained. 
The above will, at any rate, furnish sufficient proof that oyster culti- 
vation, according to the methods described, can be carried on very 
successfully in the Zeeland waters. It is very difficult, however, to 
answer satisfactorily the question, Why the same methods which on the 
Duteh coast have been productive of such good results have proved 
entire failures on the German and English coasts? As far as I can see, 
there are three causes which contribute to this result: (1) the happy 
idea of our government to rent out the Zeeland oyster-beds in small 
portions; (2) the fine business qualities of the men who engaged in this 
enterprise with genuine Dutch perseverance, simplicity, and zeal; and 
(3) the quality of the bottom, and the exceedingly favorable conditions 
of temperature and tide. The three last-mentioned causes are the ones 
to which these favorable results are mainly owing, and I therefore 
regret it all the more that I am not able to give further information on 
this subject. 
In this short article it was only my purpose to direct the attention 
of other nations to oyster cultivation as carried on in the Netherlands. 
As regards statistical data and exhaustive descriptions of the methods 
employed, I refer the reader to the respective reports. 
CIRCULAR OF THE NETHERLANDS ZOOLOGICAL ASSOCIATION. 
e HONORED Sir: The Commission of the Zoological Station intends 
during the coming summer months to inaugurate a series of investiga- 
tions, on as extensive a scale as possible, relative to the anatomy, prop- 
agation, development, mode of life, &c., of the oyster. From the second 
half of April opportunity will be offered both at the principal station 
at Bergen op Zoom and at the branch station at Wemeldinge in South 
Beveland, to make such investigation. 
A number of persons having already declared themselves willing to 
take part in these investigations, the commission is of opinion that a 
division of labor would greatly increase the chances of a favorable re- 
sult, and I have therefore been directed to request that you will take 
an active part in these investigations. The commission will supply 
you with all the aids necessary for such an investigation, excepting opti- 
cal instruments; and I would ask you, in case you should be inclined 
to comply with this request, to inform me as soon as possible. 
The only condition imposed upon you by the commission in asking 
you to share in this undertaking is that you will consent to furnish us, 
after the investigations have been brought to a close, with as full a re- 
port as possible, accompanied by the necessary illustrations, We., and 
in shape for publication. It is impossible for the commission to state 
at the present time in what shape the results of your investigation will 
