THE FISHES 



OF THE 



OLD RED SANDSTONE OF BRITAIN. 



Paut I.— the CEPHALASPIDJ]. 



INTRODUCTION. 



I WOULD here beg to claim indulgence for the deficiencies of the following pages 

 relative to the CephalaspiDtE. These Fish I have had to treat systematically for the first 

 time since the work of Agassiz ; a great deal of the material submitted to me has been 

 quite new ; and, in addition to the absence of any previous essays on the Family (except- 

 ing occasional papers of great value, but of limited scope), the very special and peculiar 

 nature of the fossils has been a source of some difficulty. The generic and other divisions 

 which I have adopted have been taken simply with the view of exhibiting breaks in the 

 continuity of forms ; and they may of course, at any time, be bridged over by further 

 discovery. At the same time, I believe that the grouping here offered furnishes the 

 most convenient method of arranging these fragmentary remains. I may mention, that 

 I feel sure, from various indications, that many new species are to be found in the 

 very localities which have furnished those now known. 



I take this opportunity of expressing my thanks to Professor Huxley for the use of a 

 great number of specimens assembled by him for his own study, as well as of specimens 

 in the Museum of the Survey ; to my colleague, Mr. Powrie, of Reswallie, Forfar, who is 

 engaged on another portion of this Monograph, for the use of his unique and beautiful 

 specimens, and other kind assistance ; to Dr. Grindrod, of Malvern ; Mr. Humphry 

 Salwey, of Ludlow ; the Rev. P. B. Brodie ; the late Mr. Wyatt-Edgell ; Mr. Lightbody, 

 of Ludlow ; the Rev. J. Crouch ; Mr. Salter ; the Rev. Hugh Mitchell ; Mr. Morton, 

 of Liverpool ; Dr. Harley, and others who have been kind enough to give their help in 

 the communication of specimens and in other ways. — E. R. L. 



