1016° REPORT OF COMMISSIONER OF FISH AND FISHERIES. [16] 
tions of the bottom temperature may not be necded for drawing up an 
exact table of the changes of temperature to which the water on the oys- 
ter beds is subject. 
The observations relative to the saltness of the water will, during the 
coming year, be brought into a more definite relation to the results of 
the observations on the current taken by the engineers. 
The two series of observations, both those on the temperature and 
those on the saltness of the water, should go on simultaneously with 
investigations as to the quantity of oyster spat, not which settles on 
this or that oyster bed, but which is found in given portions of the water 
of the Scheldt. We do not conceal from ourselves the great difficulty 
of investigating this latter point, but we feel convinced that this will 
be the most certain way of obtaining really reliable results. During 
the course of the winter we propose to study out a method by which 
such investigations could be made. The experiments in that direction 
made in 1881 have not yet led to results definite enough in their charae- 
ter to enable us to make a final decision as to the best method of carry- 
ing on these observations. Simultaneously with these investigations 
careful observations should be taken of the quantity of oyster spat 
found on the different beds during the year, not only on the so-called 
“tile beds” (where tiles are employed as collectors), but also in different 
parts of the eastern Scheldt. 
We have been informed by many persons of experience in these mat- 
ters that circumstances of a local character (still water near the main 
eurrent, the emptying of two currents, as at the Hendracht, deep 
holes in the bottom, &c.) are considered to have great influence on the 
settling of the spat; and this also formed the starting point of some of 
our consultations with the engineers in regard to observations on the cur- 
rent. We shall refer to this matter more fully in our final report; here 
we will only mention what has been communicated to Mr. van Kervel 
relative to the settling of spat on those portions of oyster beds where 
his observations were taken. (See the table.) 
(1.) The portion of lot 324, near the pit or hole, is considered to be 
very favorable to the settling of oyster spat, especially near the edge 
(more particularly the northern edge), and also along the upper portion 
of the steep walls of the hole. 
In the deep portion of the hole very few oysters are found. (See 
table, column of observations, relative to the nature of the bottom). 
On the portion of lot 324, referred to, no oysters are planted. 
(2.) Oyster spat settles very freely south of the ‘‘ Laagte.” 
(3.) Oyster spat settles in considerable quantities in the northeastern 
portion of lot 267, and seems to flourish better there than in the north- 
western portion of lot 266. 
(4.) Also in lot 231 and in its vicinity oyster spat is said to settle very 
freely. 
(5.) It is well known that large quantities of oyster spat settle in the 
