Septembek 27, 1907] 



SCIENCE 



405 



Family Ploceidte — Weaver Birds. Family 

 Alaudidffi — Larks. Family Oxyruncidse — 

 Sharp-bills. Family Tyrannidfe — Tyrant 

 Flycatchers. Family Pipridse — Manakins. 

 Family Cotingidse — Chatterers. Washing- 

 ton : Government Printing Office. 1907. 

 Bulletin of the United States National 

 Museum. No. 50 — 8vo, pp. xxii + 973, pi. 

 i.-xxsiv. 



As shown hy the above transcript of the 

 title-page. Part IV. of this monumental work 

 includes the last six families of the Oscines 

 and the first four families of the Mesomyodi. 

 Two of these, the Sturnidas and the Ploceidfe, 

 are represented in America only by introduced 

 species — the first by the common starling of 

 Europe, of casual occurrence in Greenland, 

 and introduced and apparently thoroiighly 

 naturalized over a considerable area about 

 New York City ; ' and the second by two 

 weaver-finches, introduced long since from 

 western Africa to Porto Pico, where they have 

 become naturalized. The Alaudidte, also 

 almost exclusively an Old World family, is 

 represented by only two genera, each with a 

 single species in America, namely, Alauda, 

 represented by the skylark (Alauda arvensis), 

 of accidental occurrence in Greenland and 

 the Bermudas, and also as an introduced 

 species at various points in the United States ; 

 and Otocoris, comprising the horned larks, of 

 which a single species is widely distributed in 

 North America, reappearing in the highlands 

 of Colombia. Other species of this genus 

 occur in Europe and Asia, extending south- 

 ward to northern Africa. The horned larks 

 have evidently been long residents of North 

 America, as shown by their wide distribution 

 and multiplicity of forms, no less than twenty- 

 five subspecies being currently recognized in 

 America alone, and several others in northern 

 Eurasia. This species shows great adapta- 

 bility to diverse conditions of environment, 

 it ranging from the Arctic barren-grounds to 

 tropical northern South America, and from 

 the most arid semi-desert areas of the south- 

 western United States and tableland of Mexico 

 to the humid coast belt of Oregon, Washing- 

 ton, and western British Columbia. While 



the extreme forms are very diverse in point 

 of size and coloration, and occupy in the 

 breeding season remote and widely different 

 physical areas, they are all connected by in- 

 termediate forms, occupying intermediate 

 areas. They are all more or less migratory, 

 and during winter several forms are often 

 found together, but in the breeding season 

 they occupy distinct ranges, and admirably 

 illustrate the law that, among vertebrates at 

 least, two closely related forms do not occupy 

 the same area. 



Of the remaining seven families treated in 

 the present volume, one, the Turdidse or 

 Thrushes, is nearly cosmopolitan, while the 

 other six are exclusively New World and 

 mainly tropical. Two — Zeledoniidse and Oxy- 

 runcidse — are monotypic, the first being for the 

 first time given family rank in the addenda 

 (p. 885), on the basis of structural characters 

 made known by Py craft during the printing 

 of the present volume. The family Zeledo- 

 niidse is allied to the mockingbirds (Mimidse), 

 and Oxyruncidse to the tyrant fiycatchers. 

 The three remaining families — Tyrannidae, 

 Pipridse, Cotingidse — are tropical American, 

 the last two exclusively so, the first with a few 

 genera ranging widely in temperate latitudes. 

 The Tyrannidse constitute one of the largest, 

 and is the most perplexing, of the families of 

 American birds. It contains upward of 80 

 genera, and more than 550 species and sub- 

 species, which have recently been arranged by 

 Berlepsch^ in seven subfamilies. They pre- 

 sent great diversity of form and habits, de- 

 veloping types that strongly suggest birds of 

 widely different families, inhabiting in some 

 cases distant parts of the globe; some re- 

 semble titmice, others kinglets, others are 

 thrushlike, and others strongly recall pipits, 

 wagtails and stonechats. As only thrushes, of 

 these several diverse types, share with them 

 the same geographic area, these resemblances 

 can not be ascribed to protective mimicry, 

 but must be regarded as adaptive parallelisms. 

 Indeed, adaptive parallelism in the develop- 



' Studien iiber Tyranniden, von Hans Graf Ber- 

 lepsch, Proo. Fourth Internat. Orn. Congress, 1905 

 (1907), pp. 463-493. 



