Vol. XXIII 

 1906 



1 Beyer, Allison, Kopman, Birds of Louisiana. 



On account of the general, as well as the purely scientific inter- 

 est involved, therefore, the ornithology of Louisiana offers its 

 greatest and most attractive problems in a study of the correlative 

 dispersal of species between this section and the remaining regions 

 of the State. 



Before considering in a general way the various types of country 

 in Louisiana, we will take up several of the factors that make the 

 southeast delta plain unlike all the other regions. The silt of 

 the Mississippi deposited over its flood plain bears no ever- 

 green conifers, and in such soil the entire coniferous tribe is un- 

 represented except for one species, the bald cypress {Taxodium 

 distichum) . The tree-growth of the delta plain is a most unusual 

 development of deciduous trees unbroken by native evergreen 

 arboreal growths except the live oak and the partially evergreen 

 water oaks. In addition to these and the cypress, the predominant 

 species of trees are red maple, ash, willow, tupelo (Nyssa uni flora), 

 and box elder (Negundo) in the wetter situations; elms (Ulmus 

 americana and U. fulva) nearly everywhere; Texas red oak in 

 rich wet woods, and in drier localities with hackberry, honey- 

 locust, cottonwood, sweet gum, and sycamore. Several species of 

 haw, dogwood, and holly are found in considerable abundance. 

 The lesser shrub growth is uninteresting, and contains but one 

 evergreen, the wax myrtle. Over a large part of the area, the but- 

 ton-bush (Cephalanthus) is the most conspicuous shrub. It will 

 be noticed that magnolia, as a native, is entirely absent from this 

 region. In fact, the tree flora, if considered from the standpoint 

 of separate species, is by no means peculiar or attractive. The 

 tupelo, the cypress, and the live and water oaks are the only trees 

 in any degree characteristic. The distinction of the extreme low- 

 lands is the conspicuousness of certain familiar trees on higher 

 ground, to the exclusion of many others equally characteristic of 

 more elevated regions. In fact, the country under consideration 

 exhibits a decided floral paucity except among certain of the cryp- 

 togamous orders. There is less peculiarity in the floral units than 

 in the exuberance of certain growths, and in the manner of their 

 distribution, combination, and adaptation. 



The topographical peculiarity of this territory is the extent of 

 its water-broken coast. The breadth of its marshes, the various 



