201 



swamps, hammocks and bottom lands, containing such trees as 

 Taxodimn disticluun, Be tula nigra, Querais launfolia, Magnolia 

 grandiflora, Liqiiidambar, Ilex opaca and Nyssa imiflora, all more 

 or "less draped with Tillandsia iisneoides. No Platamis was seen, 

 probably for the same reasons that it is almost wanting in the 

 pine-barrens of Georgia and Alabama, even along the larger 

 rivers.* Between the Pearl River and Lake Pontchartrain are 

 extensive flat wet pine-barrens, very much as in the maritime 

 counties of Georgia. t Piniis Elliottii, which comes within two 

 or three miles of the river on the Mississippi side, was not seen 

 in Louisiana, where P. Taeda largely takes its place (as it does 

 also in the Carolinas). Here I noticed Taxodimn imbricaritun X 

 for the first time on this trip, a few specimens between Alton and 

 Slidell. 



On approaching Lake Pontchartrain the pine-barrens pass 

 rather suddenly into salt (or brackish ?) marshes, without any 

 other "plant-formation" intervening. The same phenomenon 

 was soon afterward observed on the Mississippi coast, though in 

 Georgia there seems to be always at least a mile of live-oak 

 hammock or something of that sort between the pine-barrens and 

 the marshes. The reason for this difference is as yet obscure. 



After crossing a few miles of marshes, five or six miles of open 

 water, and then a few miles of cypress swamps, New Orleans was 

 reached. The country around New Orleans is of course very 

 flat, and the surface all Quaternary alluvium. During my stay 

 there the only natural plant-habitats which I was able to find in 

 the vicinity were the cypress swamps. These are doubtless well 

 known to most of the botanists who have visited New Orleans or 

 resided there, but they are rarely if ever adequately described. 

 They probably once covered the whole country for miles around, 

 except the slightly higher areas near the river which are said to 

 have formed§ natural levees. Going due north from the city to 



*See Bull. Torrey Club 32 : 147. 1905. 



t See Ann. N. Y. Acad. Sci. 17 : 19-20. 1906. 



+ See Bull. Torrey Club 29 : 383-389, 393-399 ; 32 : 105-I15. 



\ In the soil survey of the New Orleans area (Field Operations of the U. S. Bureau 

 of Soils for 1903) these swamps are mapped as " Sharkey Clay" and " Muck," and 

 are said to cover about 68 per cent, of the area around New Orleans. A crude 

 description of their vegetation is also given. 



