WALL-BIRD— WARBLER 1019 



M. rail (by some mistakenly called M. cavipestris), which, though 

 very generally distributed throughout the country, is much less 

 numerous than the Pied Wagtail, and more addicted to wet 

 meadows ; but, just as M. lugubris is regarded by some as a local 

 form of the more widely-ranging 31. alba, so does 31. rail hold the 

 same relation to 31. flava, the Blue-headed Wagtail, which has a 

 very extensive distribution in the Old World, and even crosses the 

 Pacific to Alaska, presenting also a great number of varieties or 

 races (most of them treated by Dr. Sharpe as real species) differing 

 from each other chiefly, if not solely, in the colour of the head, a 

 character which in this section can hardly be deemed specific, while 

 their geographical range intersects and inosculates in a most 

 puzzling manner. Credit is due to the author just named for the 

 enormous trouble he has taken, after study of a vast series of speci- 

 mens, to clear up the questions herein involved ; but it will probaljly 

 be long before ornithologists can agree on many of the disputed 

 points, and it is certain that the last word has by no means been 

 spoken concerning them. 



WALL-BIRD, a common local name of the Spotted Flycatcher 

 (p. 274) ; WALL-CREEPER see under Tree-Creeper (p. 986). 



WARBLER, the name bestowed in 1773 by Pennant (Gen. Birds, 

 p. 35) on the birds removed, in 1769, by Scopoli from the Linnsean 

 genus 3fotaciUa (Wagtail) to one founded and called by him Sylvia, 

 — the last being a word employed by several of the older writers in 

 an indefinite way, — that is to say, on all the species of 3-IotaciUa 

 which Avere not Wagtails. " Warbler " has long been used by Eng- 

 lish technical writers as the equivalent of Sylvia, and consequently 

 generally applied to all members of the Family Si/lviidx thereon 

 raised, which has since been so much subdivided as to include a vast 

 number of genera, while species almost innumerable have from time 

 to time been referred to it. 



Until recently ornithologists had come to agree pretty well as to 

 which forms should be considered to belong to the Family Sylviidds, 

 — the " American Warblers " {Mniotiltidm), to be presently con- 

 sidered, being therefrom segregated ; but some writers, seeing the 

 difficulty of separating the remainder from the Turdidse (Thrush), 

 tried to get over it by proposing to erect an intermediate Family 

 for the Wheatear and some similar forms, under the name Saxi- 

 colidse.^ But the affinity, seeming or real, to the Tmdidse does not 



^ In truth the difficulty was thereby doubled, for, if it was before hard to dia- 

 tinguisli between Sylviidee and Turdidai, it has since become harder to dis- 

 tinguish on the one hand between Sylviidse and Saxicolidm, and on the other 

 between Saxicolidaz and Turdidas. The confusion thus caused is chiefly due to 

 the adoption in a more or less modified form of the views put forth by Sundevall 

 in 187^, and revised by him in 1874 (c/. Introduction). For him, however, it is 



