NOTE. 



The number of the Genera of Fishes at present recorded in the 

 British Fauna amounting to 124, it naturally suggested itself 

 that by pourtraying two fishes on each of the 68 Plates of our 

 two Volumes, one specimen at least of every Genus might be pre- 

 sented for the examination of the Reader. Accordingly, many 

 montlis ago, along with the manuscript to the Print®*, a List of 

 Plates was put into the hands of our accomplished Draftsman, 

 in which this arrangement was prescribed; the Letter-press at 

 the same time containing express references to the pi'oposed plan. 

 The Printer speedily executed his part of the work; but the 

 Draftsman found it impossible to fulfil his task in a way that 

 would be creditable to his Art, and in keeping with the general 

 plan of the Work. We mention these details as the shortest ex- 

 planation of the discrepancy which will be found between the 

 references to the Plates in the Letter-press of this Volume and the 

 Plates it contains. They are chiefly in the way of omission, several 

 fishes being stated to be exhibited which it was found impossible 

 to introduce. The Reader, accordingly, will have tlie kindness 

 to take as his guide for the Plates, not so much the Letter-press, 

 as the following Contents, which contain a correct List of those 

 it has been found practicable to introduce. 



CONTENTS. 



PAGE 



Memoir of Rondelet . . . .17 



Introduction, ..... 45 

 Bearing on the Structure of Fishes : — 



Structure of the Lancelot . . . 46 



Electric Organ of the Silurus ... 52 



Gill-cover of the Siluridse ... 57 



Lymphatic Hearts .... 58 



