The Orizaba Group in the American Museum of 

 Natural History 



THE last addition to the series of panoramic bird groups in the American 

 Museum of Natural History might be called a Faunal Group rather 

 than a Habitat Group, the term which has been applied to its prede- 

 cessors. Unlike them, it is not designed to show one or more species of a 

 definite locality, but the more characteristic species of a faunal area, — namely, 

 the forest-inhabiting species of tropical eastern Mexico. It is also intended to 

 serve as an object-lesson, in the influence of altitude on the distribution of 

 life. 



The obser\-er is supposed to be standing in the dense tropical forests which 

 clothe the foothills of the Sierras. In the luxuriant tropical vegetation about 

 him are Parrots, Toucans, Trogons, Motmots, and other equally characteristic 

 tropical birds, and from their home he may look 10,000 feet upward to the 

 Boreal Zone on ]SIt. Orizaba, where, in the grand forests of pines and spruces, 

 Crossbills, Evening Grosbeaks, Juncos, Brovin Creepers, and other northern 

 types of birds, are nesting. 



To encounter so radical a change, at sea-level, would require a journey 

 at least to northern ]Maine. Here the change is occasioned by altitude rather 

 than latitude, and an altitudinal journey of less than three miles produces as 

 striking a faunal difference as would a latitudinal one of 3,000 miles. Indeed, 

 one might travel from the Equator to the Poles without experiencing more 

 profound variations than one finds in passing from the Tropical Zone, at the 

 base of the mountains, through the Temperate Zone on their sides, to the Boreal 

 Zone above; and thence, beyond the limit of life, to the everlasting snows 

 which crown the summit of Orizaba (alt. 18,225 feet). 



It is aimed to demonstrate the significance of the facts depicted in the 

 group by the use of large colored transparencies, set one above the other in 

 panels on each side of the group, and at a proper distance from it. These 

 transparencies were made from photographs representing t3^ical scenes in 

 the Tropical, Temperate, and Boreal Zones, and above timber-line. At the 

 bottom is the picture on which was based that part of the paintiag which shows 

 the tropical forests. Above it is a Aiew in the oaks of the Temperate Zone, 

 and OA-er this are pictures in the pines and spruces, and among the rocks and 

 snow above timber-line. These pictures thus supply details of the Adew con- 

 tained in the background, and form, as it were, a vertical section in the Sierras 

 from sea-level to snow-line. 



The accompan3"ing photograph merely suggests the method of treatment, 

 without conA-e\*ing a true impression of the unusual beauty of the group itself 

 or of the illusion of depth and distance which has been created. — F. M. C. 



(9/ 



