INTRODUCTION. V 



less to say that through their kind assistance in revising the 

 details now presented to the reader, a greater accuracy has 

 been ensured than could possibly have been the case had the 

 author relied solely upon his own efforts. 



The results which follow from a consideration of these 

 details are both curious and instructive. 



When the late Mr. Yarrell, in 1856, published the third 

 edition of his ' History of British Birds, ' he enumerated 352 

 species which he considered had more or less claim to be in- 

 cluded in the British list. Since that time no less than 47 

 others have been added*, so that the total number of species 

 at present recognized as occurring in Great Britain should be 

 399 ; but leaving out four of those noticed by Yarrell viz. 

 Cygnus olor, a domesticated species, Uria ringvia (p. 74) 

 and Larus capistratus (p. 175), which are mere varieties, and 

 Alca impennis, now believed to be extinct the corrected total 

 arrived at is 395. 



Of these, in round numbers, 130 are Residents, 100 Perio- 

 dical Migrants, and 30 Annual Visitants, the remainder being 

 Rare and Accidental Visitants. And here it may be well, in 

 order to avoid future misunderstanding, to define the terms 

 which have just been employed. 



As RESIDENTS are included those species which rear their 



* These are : Falco islandicus, Astur atricapillus, Milvus migrans, 

 Buteo lineatus, Nyctale acadica, Lanius minor, Muscicapa parva, Vireo- 

 sylvia olivacea, Turdus atrigularis, T. sibiricus, Salicaria palustris, S. 

 aquatica, Regains calendula, Motacilla cinereocapilla, Anthus spinoletta, 

 A. cainpestris, A. cervinus, A. ludovicianus, Alauda calandra, A. sibirica, 

 Emberiza pusilla, E. rustica, E. melanocephala, Fringilla serinus, Carpo- 

 dacus erythrinus, Sturnella magna, Picus medius, P. villosus, P. pubescens, 

 P. auratus, Cuculus erythrophthalinus, Hirundo bicolor, Cypselus cauda- 

 cutus, Caprimulgus ruficollis, Syrrhaptes paradoxus, ^Egialitis vociferus, 

 Totanus solitarius, Gallinago wilsoni, Grus virgo, G. pavonina, Crex 

 Carolina, Cygnus aniericanus, C. buccinator, Anser albatus, Sterna velox, 

 Larus ichtbyaetus, and Larus melanocephalus. 



