1904.] Allen, Mammals from Santa Marta, Colombia. 411 



the mountain forest. On ridges and hills, especially in 

 Manzanares valley, the trees often disappear altogether or 

 grow scattered over the open grass lands. 



I have been thus explicit in describing the two kinds of 

 forest because they exist in all parts of tropical America, and, 

 in my opinion, the distinction is interesting and significant. 

 The ' pampa ' of the Santa Marta district is the ' campo ' and 

 'coatinga' of Brazil, and the scrubby growth of lower hills in 

 the West Indies ; a modified form is the ' chapparal ' of Mexico. 

 Everywhere the plants are different from those of the swamp 

 forest ; generally the trees are lower, often small and gnarled 

 and sometimes scattered; and everywhere they shed their 

 leaves during the dry season. The difference does not always 

 correspond to a difference of soil or situation; the two kinds 

 of forest may adjoin each other on level ground or on a moun- 

 tain side, on land equally dry or humid. 



It is impossible to avoid the impression that the dry forest 

 is an old, stunted, and worn out vegetation, tending to ex- 

 tinction, while the swamp forest, with its exuberant growth, 

 is plant life in the vigor of youth. Such impressions cannot 

 be accepted as scientific truths, yet they may point in the 

 right direction. It appears certain that the swamp forest is 

 gradually encroaching on the other; this can be observed 

 nearly everywhere. It is possible that the dry forest, with 

 its open lands or 'campos,' represents an older flora. 



As yet we have no comparative lists of the plants; and 

 until these are drawn up and we know more about the ter- 

 tiary and quaternary floras of South America we can reach 

 no definite conclusions on the question. As animals pass 

 readily from one kind of forest to the other, it may be impossi- 

 ble to determine their original habitats; yet certain species 

 and groups can be assigned with some confidence. To the 

 dry forest region, for example, belong the deer with branched 

 horns (except C. palustris [ = Odocoileus palustris], which is 

 an inhabitant of the river plains), all the tropical American 

 Canidae, hare, and all, or nearly all, the armadilloes. The 

 puma and one or two unicolored cats affect the dry forest. 

 The ostrich, common in the interior of Brazil, lives exclusively 



