PREFACE 3 



led him to suggest to me wherein scale reading might be of value in 

 confirming as fact what had otherwise remained very much in the region 

 of theory. For example, I do not think I could have realised how 

 protracted the young sea-trout's residence in fresh water might be before 

 migration without Mr. Hutton's valuable help. I am further indebted 

 to him and to his skill with the camera for all photographs of scales 

 and for most of the photographs of fish reproduced. To him, also, 

 and to the Rev. Alex. Slater Dunlop, B.D., Minister of Luss, I am 

 indebted for a revision of the proof sheets. 



As to the other illustrations, failing any skill with the camera, I have 

 perforce had to fall back upon such drawings as I could myself accom- 

 plish with pen and brush. They are intended to be viewed rather as 

 diagrams than pictures, diagrams which can be conveniently compared 

 one with another. 



In spite of its many defects I hope this monograph may help to 



induce others to apply themselves to a study of one of the most 



interesting of our British fishes. 



H. L. 



Glasgow, i,v/ February, 1916. 



