6 Annals of the Carnegie Museum. 



for an abstract of the geological and botanical matter respectively 

 found in this last article. Our acknowledgments are also due to the 

 following parties for their courtesy in the loan of specimens required 

 in this connection : Dr. Frank M. Chapman and Mr. Waldron DeWitt 

 Miller of the American Museum of Natural History; Dr. Witmer 

 Stone of the Academy of Natural Sciences of Philadelphia; Dr. 

 Charles W. Richmond of the U. S. National Museum; Mr. E. W. 

 Nelson of the Bureau of Biological Survey; the late Mr. Charles B. 

 Cory of the Field Museum of Natural History ; Messrs. Outram 

 Bangs and Thomas E. Penard of the Museum of Comparative Zool- 

 ogy; and Mr. James H. Fleming of Toronto, Ontario. In addition, 

 Mr. Bangs and Dr. Richmond have aided us by forwarding data for 

 specimens in the collections under their care, and by making certain 

 suggestions and criticisms of value. Dr. Harry C. Oberholser has also 

 given assistance of this latter kind. The originals for the plates and 

 maps which accompany this report have been prepared by Mr. George 

 M. Sutton under the direction of the senior author. And finally, we 

 have to thank Mr. Wilmot W. Brown and the late Mr. Herbert H. 

 Smith (and Mrs. Smith) for much detailed information of value con- 

 cerning their work in this region, particularly with reference to the 

 localities where they collected. Mr. Smith's published account of the 

 region (in Allen, Bulletin American Museum of Natural History, 

 XX, 1904, 408-414), has also been very useful. 



Geography and Physiography. 

 Geographical Limits.^ — The Department of Magdalena comprises 

 that part of the Republic of Colombia lying between the Magdalena 

 River and the Venezuelan boundary, fronting on the Caribbean Sea, 

 and with a narrower strip extending south to a line a little below the 

 eighth parallel of north latitude. On its extreme northeastern frontier 

 lies the Goajira Peninsula, a low, sandy, arid region, constituting the 

 northernmost point of the South American continent, thrust out be- 

 tween the waters of the Caribbean on the one hand and those of the 

 Gulf of Maracaibo on the other. Omitting this area in general from 

 consideration, our main concern is with the northern portion of the 

 Department in question, comprising an area roughly triangular in 

 outline, bounded on the north by the Caribbean Sea, on the west by 

 the swamps of the Magdalena Delta, and on the southeast by the 



