6 



to note that of the 290 species of grass here listed no less than 

 169 have a range northern enough to be included in Britton. 

 & Brown's manual; i. e., to the southern boundary of Virginia 

 and Kentucky. About twenty-five species seem to be undoubt- 

 edly introduced European species, and some six or eight Asiatic, 

 but the writer has not been able to decide exactly how many 

 species are native and how many are introduced from elsewhere. 



The following species, according to Prof. Small's Flora, 

 occur in Louisiana only of the United States : Panicum proa 

 tratum, Luziola Peruviana, Trisetum Loudovicianum, Leplo 

 chloa scabra, Vetiveria Zizanioides. 



A comparison with the grasses of Alabama as set forth by 

 Dr. Mohr shows that the two States have about the same number 

 of grasses, though no doubt Alabama has been much more 

 thoroughly explored than Louisiana, which may eventually 

 prove to have a good many more. Of these, 190 species, or 

 about 65 per cent, occur in both States, the proportion of 

 grasses to the whole flora also seems to be nearly the same 

 in both, perhaps slightly larger in Louisiana. According to 

 Dr. Mohr grasses form somewhat over 11 per cent of the flora 

 of Alabama, while of the writer's collection of Louisiana 

 plants, grasses form about 12 per cent. 



The accompanying notes relative to the distribution of 

 grasses in the State are necessarily extremely imperfect and 

 many of the grasses are distributed much more widely over 

 the State than the writer has observed them. 



In conclusion, the writer desires to express his thanks to 

 the Board of Managers of the Gulf Biologic Station for sub- 

 stantial help during the past two years in collecting material, 

 and especially to Prof. B. H. Guilbeau, the Director of the 

 Station, at whose suggestion this paper has been prepared, 

 for every courtesy and assistance. 



POACEAE (GRAMINEAE). GRASS FAMILY TRIPSA- 

 CUM L. SYST PL. ED. 10, 2 : 1261. 1759 



Tripsacum dactyloides L. — Britton & Brown, Illus. 

 Flora, Vol. I, 98, Fig. 210. Small Flora 53. Beale 18, Fig. 3. 



Am. Grasses I, 7, Fig In wet or swampy soil in all 



parts of the State. 



