IXTEODrCTIO>-. 



Mr. Selby's catalogue incliTdes all the birds of the two coun- 

 ties that were known up to the time of its publication, and was 

 a step far in advance of what had previously been done. But 

 since its publication upwards of forty years have elapsed, and 

 duiing that period a considerable number of species have been 

 added to the list ; and the information as to the avifauna of the 

 district has in every way been greatly advanced. Such addi- 

 tional matter might perhaps have been given as an addendum, 

 or as it were in continuation of this catalogue ; but to have done 

 so would not have been satisfactory. 



The readiest and simplest plan for me appears to be to draw 

 up an entirely new catalogue, incorporating with it every thing 

 of importance mentioned in the labours of my predecessors. 



For many years past I have kept a journal in which is care- 

 fully registered the occurrence of all rare and remarkable birds 

 in the two JSTorthern Counties, and all other matters of interest 

 respecting the avifauna of the district. This journal will form 

 the basis of the catalogue; and I have also availed myseK of 

 the assistance of my brother ornithologists of the neighbourhood, 

 to whom my best thanks are due, for the cordial cooperation 

 they, one and all, have afforded. My acknowledgments of such 

 assistance will be more particularly made, under the heading of 

 each species, in the body of the catalogue. 



In Mr. Selby's catalogue two hundred and fourteen species are 

 recorded : this new catalogue contains about two hundi-ed and 

 sixty-five, thus adding more than fifty to the former. The total 

 number of species of British birds is, according to the latest 

 authorities, about three huncbed and ninety-five, being only one 

 hundred and thirty more than have occurred in the counties of 

 Northumberland and Durham; so that oui- list now contains 

 about two-thirds of the whole number of the British species. 



The ornithic richness of the district does not fall far short of 

 that of Xoi-folk, a county of which the ornithology has been well 

 worked out for many years, and in which the avifauna is veiy 

 extensive. Mr. Homy Stevenson states, in a note in the first 

 volume, page 14, of his work on ''the Bii'ds of Ts^^orfolk," that 

 there are two hundred and ninety-one species in that county; 



