Xii PREFACE. 



and White Creeper (Mniotilta varia) and the Black-throated 

 Green Warbler (Dendroeca virens). But the strangest example 

 of this sort I have noticed I think was the case of an Oriole 

 (Icterus Baltimore) that I heard at Ipswich last season. So 

 different were its notes from the common notes of the Balti- 

 more that I failed entirely to refer them to that bird till I saw 

 its author." 



"Aside from such unusual variations as this, which we may 

 consider as accidental, birds of unquestionably the same spe- 

 cies, as the Crow, the Blue Jay, the Towhe 10 and others, at 

 remote localities, as New England, Florida, Iowa, etc., often 

 possess either general differences in their notes and song, 

 easily recognizable, or certain notes at one of these localities 

 never heard at the others, or an absence of some that are else- 

 where familiar. This is perhaps not a strange fact, since it is 

 now so well known that birds of the same species present cer- 

 tain well marked variations in size according to the latitude 

 and elevation above the sea of the locality at which they were 

 born, and that they vary considerably, though doubtless within 

 a certain range, in many structural points at one and the same 

 locality. In other words, since it is known that all the differ- 

 ent individuals of a species are not exactly alike, as though all 

 were cast in the same die, as some naturalists appear to have 

 believed. 



" Certain irregularities in the breeding range of birds have 

 also come to light. It is perhaps not remarkable that a pair 

 of birds of species that regularly breed in northern New Eng- 

 land should now and then pass the summer and rear their 

 young, in the southern part, as has been the case in certain 

 known instances in the Snow Bird (Junco hy emails) , the Pine 

 Finch (Chrysomitris pinus), and the White-throated Sparrow 

 (Zonotrichia albicollis) ; but it is otherwise with the Snow 

 Bunting (Plectrophanes nivalis) , "which rarely breeds south of 

 Labrador, of which there is a single well authenticated instance 



It is to be remarked that a variety of this bird has recently been found in 

 Florida. 



