244 , Recent Literature. [April 



from the Tropical zone immediately below while the species characteristic 

 of the last two have originated in the same zones at sea-level farther south. 

 Many of these species moreover range north over the entire temperate 

 zone with little or no modification which should be expected, since they 

 have nowhere left the peculiar environment of their original zone. Species 

 of the Subtropical zone on the other hand have pushed up from their 

 original Tropical zone into an entirely different environment with the result 

 that they have in nearly every instance been materially modified. Or as 

 Dr. Chapman puts it: " Uniformity of life increases with altitude." The 

 Cauca Valley, the fauna of which differs decidedly from that of the humid 

 Pacific coast, Dr. Chapman considers to have been under water until 

 post-tertiary time so that its bird-life is of comparatively recent Origin. 



Another interesting fact brought out in the work before us is the curious 

 break in the Subtropical forest zone, which extends along the Andes to 

 northern Colombia and is then lacking until we reach the high mountains 

 of western Panama and Costa Rica, where the same types, sometimes 

 the very same species, reappear. This break Dr. Chapman calls the 

 " Panama fault," and cites evidence to show that a former connecting 

 range of high mountains, which carried the Subtropical zone over the 

 present tropical interval, has been entirely reduced by erosion and subsi- 

 dence in comparatively recent geological time. 



The chapters treating of these and other distributional problems, with 

 their host of original facts and faunal lists of species will be studied with 

 the deepest interest by all zoogeographers, while the itineraries of the eight 

 expeditions, illustrated as they are by numerous admirable photographs, 

 are fascinating reading for anyone interested in travel and exploration. 



The systematic portion of the report based upon the collection of 15,775 

 skins secured by Dr. Chapman and his assistants, treats of 1285 species 

 and subspecies of which 22 new species and 115 new subspecies have 

 been described by the author in the course of his studies of this extensive 

 material. Most of these were described in previous papers but eleven 

 appear in the present volume for the first time, while for convenience the 

 earlier diagnoses are all reprinted here. One of the novelties discovered 

 by the expeditions is named Troglodytes mvsculus neglectus (p. 520). This 

 name, as has been pointed out to us by Dr. Charles W. Richmond, is pre- 

 occupied by Troglodytes neglectus Brooks, an Old World form of Winter 

 Wren, and it becomes desirable to give it a new name. It seems to us 

 that Troglodytes musculus chapmani would be a fitting name for this Wren 

 and we therefore propose this as a substitute for T. m. neglectus Chapman. 



The various species in Chapman's report are numbered in accordance 

 with Brabourne and Chubb's ' Birds of South America.' The synonymy 

 includes a reference to the original description of the species with type 

 locality, and other references to its occurrence in Colombia. This is fol- 

 lowed by critical remarks upon range and relationship and a list of localities 

 from which specimens were secured. Dr. Chapman estimates that the 

 whole number of Colombian birds would be about 1700. While we fully 



