Vlll PREFACE. 



and to afford abundant work to any naturalist whose 

 time and opportunities allow of his taking them in 

 hand" (Vol. I, p. 2). The present Monograph is the 

 result of an endeavour to enumerate and describe the 

 species which Dr. Brady has excluded, and may there- 

 fore be regarded as supplementary to that author's 

 work. 



The Copepoda recorded by Dr. Baird as parasites 

 on British fishes number thirty-four species ; this 

 number is now increased to one hundred and thirteen. 

 Many of the new records are scattered through various 

 publications, and it has been considered by the Council 

 of the Ray Society that, for the convenience of 

 students, these should be brought together and 

 combined with those described by Dr. Baird, and thus 

 made more accessible. This work, which has been 

 intrusted to us, we have endeavoured to carry out, 

 and we hope, while conscious of its imperfections, that 

 it may be found useful and tend to create a still 

 greater interest in the study of these remarkable 

 organisms. 



In the preparation of this Monograph we have been 

 indebted for valuable assistance to numerous friends, 

 and to none more so than the Rev. Canon A. M. 

 Norman. Indeed but for his encouragement and 

 assistance it is doubtful if we could have ventured to 

 undertake it. We therefore embrace this opportunity 

 of expressing our gratitude to him, not only for his 

 helpfulness in this special work, but also for kindness 

 shewn to us in many other ways. We are also 

 indebted to Dr. Williamson and Dr. Bowman of the 

 Scientific Staff of the Fishery Board for Scotland for a 

 number of rare and interesting specimens; and to 

 our friend Mr. John Lindsay (of Messrs. Blackwood & 

 Sons, Edinburgh) for assistance in revising the proof- 

 sheets and other useful help. Our grateful acknow- 

 ledgments are also due to Mr. John Hopkinson, 

 Secretary of the Ray Society, for the great labour and 

 interest he has taken in seeing the work through the 



