35 



LICHENS. 



The following' s{)eeies of lichens were collected mainly along 

 the beach. They were determined for the writer by Mr. A. G. 

 Merill, of Rockland, Maine : 

 Graphis scripta Ach. 

 Physcia stellaris (L.) var. aipolia Xyl. 

 Usnea florida (L.) Ach. 

 Ramilina sub fraxinea Nyl. 



ALGAE. 



Tw'O species of Algfe were collected, which both occur con- 

 stantly associated together in the shallow pools on the jetties : 

 Enteromorpha compressa (L.) Grev. 

 Ectocarpus Mitchellae Harvey. 



Dr. Farlowe suggests that Ectocarpus ]\Iitchellae is 



identical wnth Ectocarpus viridescens Fleuret. 



NOTES OX S0:ME new and little KNOAVN SPECIES 



COLLECTED IN THE PRAIRIE REGION OF 



SOUTHWEST LOUISANA. 



In traveling w-estward from New Orleans on the Southern 

 Pacific, the flora shows no marked changes as long as one is in 

 the alluvial sugar regions, but soon after passing Lafayette one 

 plunges almost abruptly into the prairie regions of Acadia and 

 Calcasieu, where rice, instead of sugar and cotton, become the 

 staple industry; and in this region the flora also changes in a 

 marked degree. Until about the year 1884, the agriculture of this 

 region was largely restricted to raising cattle and horses on the 

 jrairie ranges. But since that date, improved machinery for irri- 

 gation and the construction of canal systems have led to the rapid 

 extension of rice cultivation, though large tracts of virgin prairie 

 still remain. Although the climatic conditions are semi-tropical, 

 the high temperature that is characteristic of localities so far 

 south is much modified by cool winds from the Gulf. It is doubtful 

 i r any part of Louisiana has a cooler and more agreeable southern 

 climate. The physical features of this area are not specially 

 marked. The elevation ranges from about eighteen to twenty-five 



