NA TURE 



[May 1 8, 1905 



sjonian fauna in the extreme south, a considerable 

 portion have invaded Norili America — possibly re- 

 occupying the home whence they had been driven 

 during some glacial period, but certainly to an extent 

 that sensibly affects the existing fauna. In the same 

 way certain characteristic forms of the Patagonian 

 fauna, diminishing in number as the distance from 

 their modern focus increases, occur throughout the 

 whole length of South America, generally clinging 

 to the slopes of the Andes, and a few reach the 

 highlands of Central America — Scytalopus, for in- 

 stance, the sole example of that most characteristic 

 Patagonian family, Pteroptochidce, which has made 

 its way into Costa Rica. 



Further into detail it would be impossible here to 

 go, for it would need the exhibition of long lists and 

 tables showing the distribution of various groups or 

 forms to make clear the truth of the statements just 

 enunciated, to which, no doubt, some will demur; 

 but it may be mentioned that their truth does not 

 rest alone on the evidence afforded by birds, for a 

 close examination of the other classes of vertebrates 

 will be found to corroborate the same position, and it 

 mav be left for time to show whether the opinions 

 here expressed are not generally accepted as true. 

 Briefly recapitulated, they are that the whole of 

 America is now occupied by three faunas. The very 

 ancient and, it may be added, morphologically low 

 Patagonian in the south ; that of a somewhat higher 

 morphological rank which peoples the greater part 

 of South America, all of Central America, and per- 

 meates almost to the middle of North America, until 

 it is outnumbered by still higher forms derived from a 

 Palaearctic stock; but to lay down ;my boundaries, 

 even phvsical boundaries, for these distinct faunas is 

 impossible, and though we may call the first and last 

 " Patagonian " and " Nearctic " respectively, it is 

 not easy to find a good title for the second, unless 

 we were to apply to it Mr. Sclater's original name, 

 " Neotropical," restricting that in the southern direc- 

 tion and extending it in the northern. It has been 

 called " Columbian " by one writer, and if that epithet 

 had not been used before in a much more limited 

 sense by another writer the name would not be 

 inappropriate, for Colombia may be regarded as its 

 modern focus, but doubtless it anciently extended 

 much further to the northwards, and by it in remote 

 times the Sandwich Islands were most likely colonised. 



If these remarks be deemed too critical, it must be 

 understood that they are not intended to be generally 

 opposed to the views of Mr. Godman. Writing of 

 the butterflies in the " Introduction " before referred 

 to, he stated expressly that the fauna of Central 

 -America " is mainlv a northern extension of that of 

 tropical South .America," with a considerable number 

 of Nearctic forms " coming down the central plateau 

 a certain distance into Mexico, and some even into 

 Guatemala." This is not only equally true of the 

 birds, but the southern extension of their northern 

 forms reaches even further. The real question is, what 

 value is to be attached to these northern forms? A 

 very slight examination will show that nearly all 

 bc-lo.ig to l.imilics that are cssentiallv Neotropical. 

 NO. 1S55, VOL. 72] 



It has been pointed out before now that the so-called 

 Nearctic " Region " has not more than one peculiar 

 familv of birds (Chamaeidse), and that a very doubtfuf 

 one. All the other families of land-birds arc either 

 Neotropical or Palaearctic, so that in one sense it may 

 be said that no distinct, or peculiar, Nearctic fauna 

 exists, the bird-population of North .America having 

 (with that one doubtful exception) wholly Palaearctic 

 or Neotropical affinities, and those often of the very 

 closest nature. No stronger corroboration of the 

 views of Prof. Huxley, Prof. Heilprin, and others. 

 who have advocated the abolition of the Nearctic 

 '" Region " can be adduced than is furnished bv Mr. 

 Godman "s tables, and when we speak of a Nearctic 

 fauna, such as exists now, we mean a mi.xed multi- 

 tude of either Neotropical or Patearctic extraction, or 

 having a common origin with one or the other of 

 those faunas. 



But it will not do here to follow further this in- 

 teresting theme, important as it is in the light that it 

 sheds on the history of the modern inhabitants of the 

 earth. Something must be said before we leave these 

 volumes of the way in which they are presented to the 

 public. Considering that upwards of 1400 species of 

 birds h.id 10 be included, the amount of space avail- 

 able for the treatment of each must necessarilv be 

 small. But here a most rigid and commendable 

 economy has been practised. No space is needlessly 

 taken u]) by considerations of laxonomv, nomen- 

 clature, or such like ancillary subjects on which sO' 

 many faunal writers deem it expedient to dilate, 

 though the first is only wanted in a general treatise 

 and the second is regarded by the wise as a snare to 

 be avoided by all who have no time to waste over 

 frivolities. By many of the younger zoologists of the 

 present day the principle of nomenclature followed by 

 the authors will be set down as old-fashioned, but 

 considering the weight of the authorities cited, and 

 their number, the application of the principle is abun- 

 dantly justified, though exception to some of the 

 results may here and there be reasonably taken, and 

 suflficient synonymy is given as to preclude any pos- 

 sible confusion. In like manner there is no attempt 

 to invent a new classification, for which, in the 

 present state of flux, all should be thankful. That 

 which has been in use by taxonomers for some thirty 

 years in respect to American, or at least South 

 American, birds is adopted. Be its faults what thev 

 may, it is well understood by the great majoritv of 

 those who have been most interested in the subject 

 during that period. The localities whence each 

 species has been recorded are dulv noted in the 

 account of it, and thus the details of its range may 

 in most cases be very fairly traced, while reference is 

 systematically made to the authoritv responsible for 

 the statement, and this, needless to say, is a very 

 important matter. Furthermore, the distinguishing 

 characters of both genera and species are presented 

 with the skill that comes only from intimate know- 

 ledge of the respective forms and careful comparison 

 of them with their allies, a feature that is often absent 

 in modern ornithological works, and in one of this 

 m.agnitude is especially to be commended. The species 



