105 



difference in vegetation confirms the difference of soil as 

 already pointed out, and the question presents itself: what is the 

 probable difference in the geological formation of these two contig- 

 uous regions of country, which apparently hate both been exposed 



to tii.' same natural causes in the formation of the surface level, and 

 both rest upon the same brown loam of the bluff? The only plausi- 

 ble solution that I can give to this question is, that the St. Landry 

 u b were formed like the marsh lands of the Attakapas country, 

 from the gradual deposits of finely comminuted materials suspended 

 in the water of the gulf marshes, and composed of lime, clay and 

 I and decayed vegetable matter. These prairies have been 

 redeemed from the gulf marshes at a much earlier period than the 

 Calcasieu prairies, and their surface soil was formed not by the grad- 

 ual recession of the gulf shore or by sudden overflows and the rapid 

 and subsidence of the tides, but by a calm surface of marsh 

 i r slightly disturbed only by the periodical flux and reflux of the 

 wat< ra of I he gulf. 



On the other hand the Calcasieu prairies were formed by the sink- 

 ing of the gulf bed and the gradual contraction of the shore line, as 

 well as sudden periodical tidal overflows of the gulf waters agitated 

 by the winds and in constant motion, depositing only the heaviest 

 materials, and sweeping there by the force of the waves the coarse- 

 grained sand slightly intermixed with clay and lime ingredients. 



In low places the waters accumulated from sudden inundations, 

 remained stationary until they were evaporated, leaving behind the 

 soil material which they held in suspense, which accounts for the 

 fertile spots in a sandy country. 



In other words the undulating surface of the Calcasieu country 

 was an insuperable obstacle for the encroaching tide waters of the 

 gulf to form marshes; but as the gulf shore once extended to where 

 the Calcasieu river divides into two branches, it gradually receded 

 by the sinking of its bed, and the waves and tides dashing towards 

 the shore left every where a layer of sand, until the whole country 

 from the Nez Pique to the low grounds where the gulf marshes com- 

 menced became a sandy plain, now covered by a crust of vegetable 

 mould produced by the accumulation of decaying vegetation con- 

 tinually reproduced for thousands of generations. 



In confirmation of the theory that the Gulf extended, within a 



