How can it best be caught? 
In what form should it be marketed? 
What size does it attain? 
What are its habits? 
What does it eat? 
How rapidly does it grow? 
Although it is quite obvious that these cannot be answered com- 
pletely, it is hoped that sufficient information will be given to form 
a proper foundation for the development. of the fishery and for its 
future conservation. 
Knowledge is power and the successful business man considers 
every aspect of the situation from the raw material to the marketing 
of the finished product before he takes up a new line. Since, un- 
fortunately, knowledge of our fishes is largely lacking even among 
those engaged in the trade, it is of much practical importance to 
present knowledge concerning any new line that it is proposed to 
introduce. We believe that the Canadian Plaice deserves to be 
one of our more important food fishes, and is a line that should be 
pushed strongly, so we give the available facts concerning it, which 
show just how valuable it should be to us if properly handled. 
No knowledge is complete and it cannot be claimed that we have 
answered all the important questions concerning this fish, but we 
believe that we are able to present so clear and accurate a picture 
of its life that it will be quite evident what measures should be 
adopted for its full utilization and proper conservation. 
Peculiar difficulties surround an investigation of the life habits 
of such a fish, seeing that one cannot observe it in its home at any 
stage in its life history. Although its eggs float near the surface 
they are so transparent as to be seen only when taken from the 
water, and the young fry, which also are transparent, have the 
curious habit of coming near the surface only at night. On the 
other hand the old fish live on the bottom in water more than a 
hundred feet in depth and so cannot be seen until they are caught 
and brought up to the surface. Since direct observation is 1m- 
practicable, we have to rely wholly upon indirect methods of ob- 
taining information. These scientific methods evolved during many 
years by a host of investigators have made it possible to give such 
a complete account as the present one of the life of this fish after 
having had only a single season for its study. 
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