TO 



SIR WILLIAM JARDINE, BARONET, F.R.S.E., F.L.S., F.Z.S , 



Member of the Wernerian Natural History Society of Edinburgh ; Honorary Member of 

 the Natural History Society of Northumberland, Durham, and Newcastle-upon-Tyne; 

 the South African Institution, Cape of Good Hope, &c. &c. 



OF APPLEGARTH, DUMFRIESSHIRE ; 



ROBERT KAYE GREVILLE, ESQ., LL.D., F.R.S., F.L.S., F.A.S.E., 



Member of the Wernerian Natural History Society of Edinburgh, of the Imperial Academy 

 Naturae Curiosorum of Moscow, of the Natural History Society of Leipsic, of the 

 Physiographical Society of Lund; Corresponding Member of the Natural History 

 Society of Paris, of the Academy of Natural Sciences of Philadelphia, of the Medico- 

 Botanical Society of London, of the Linnean Society of Normandy ; Honorary Mem- 

 ber of the Royal Irish Academy, of the Lyceum of Natural History of New Yoik, of 

 the Natural History Society of Montreal, of the Liverpool Royal Institution, of the 

 Cambridge and York Philosophical Societies, &c. 



OF EDINBURGH ; 



AND 



PRIDEAUX JOHN SELBY, ESQ., M.A., F.R.S.E., F.L.S., 



Member of the Wernerian Natural History Society of Edinburgh ; Vice-President of the 

 Natural History Society of Northumberland, Durham, and Newcastle-upon-Tyne; 

 Honorary Member of the Royal Zoological Society of Ireland, the Yorkshire Philo- 

 sophical Society, the Bristol Institution, &c. 



OF TWIZELL HOUSE, NORTHUMBERLAND. 



To whom, in conjunction with the individuals whose names occur in a 

 succeeding page, can T dedicate this work with so much propriety, as to 

 those, whose researches as Naturalists, and philanthropy as Men, equally 

 command admiration and esteem ; since, but for their unwearied exertions 

 in obtaining patronage for my humble labours, these pages might never 

 have met the Public eye ? 



To them, therefore, in testimony of the feelings with which he shall 

 ever remember their prompt assistance, this Monograph 



Is most respectfully inscribed by 



THE AUTHOR. 



