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DEPARTMENT OF THE NAVAL SERVICE 



6 GEORGE V, A. 1916 



in this solution, for if left too long they fall to pieces and sometimes even completely 

 dissolve. The time varies greatly with the saturation of the solution and the condition 

 of the scales, depending lal-gely on the amount of previous soaking in water. They 

 were next washed in three changes of water, which should remove all the slime and 

 dirt as well as the KOH. They are next transferred to 95 per cent alcohol, in which 

 they need only remain a few minutes, when they may be mounted on slides. If the 

 scales are of a fair size, it is best, at this stage, to look at them with a binocular 

 microscope and pick out the best, for always a proportion of them are injured and 

 are not good for age-determination. The alcohol next is drained off and they are 

 placed on miscroscopic slides, ten to twenty from each fish. But if the scales are 

 small, as is often the case, and there are a great many to be studied, it is most con- 

 venient to float them on the slide and drain off the alcohol. Before the scales become 

 dry enough to curl up, another slide, lightly smeared with glue at the ends should be 

 placed over them and firmly held there until the glue sets. We found that four spring 

 clothes-pins, clipped on to the two ends, served this purpose admirably. When the 

 glue is set, which usually takes several days in the New Brunswick climate, the scales 

 are ready for microscopic study. 



The following is a list of the fish, which (excepting where otherwise stated) were 

 all taken on baited trawls, showing where and when caught : — 



North Channel, June 12. '' 



North Channel, June 15. 



