480 PHANEROGAMOUS PLANTS. 



the genus that we have seen from the Pacific coast, -It extends 

 across the country from the southern Atlantic States to California. 

 It forms long and strong creeping rhizomes, and frequently occurs in 

 collections from the Pacific coast without inflorescence. 



7. PANICUM, Linn. 



1. Panicum agrostoides, Spreng. 



Hab. On the Sacramento, California. — This species from the At- 

 lantic States occurs in the collection of the Expedition, but in no 

 other from the Pacific coast that we have examined. 



2. Panicum capillare, Linn. 



Hab. On the Sacramento, California. — Some of the forms of this 

 species seem to be enough unlike the type to take at least the rank 

 of a variety ; but an extensive suite of specimens, collected at various 

 stations from the Mississippi to the Pacific, shows that as it goes west- 

 ward the plant becomes more robust, the branches of the panicle less 

 capillary, and the mostly short-pedicelled florets larger and more 

 acute. 



3. Panicum scoparium, Lam. 



Panicum scoparium, Lam. Encycl., 4, p. 744. 

 P. pauciflorum, Ell. ? Gray Man. ed. 5, p. 648. 



Hab. Oregon.— Collected also by Spalding and Hall. This species, 

 which occurs in the Eastern States, like the related P. dichotonum, 

 assumes a variety of forms, and late in the season branches and some- 

 times becomes very puzzling. It is readily distinguished by a fold or 

 crease at the base of the lower palet of the perfect floret, which is, 

 under a strong lens, minutely dotted in lines. 



4. Panicum Crus-Galli, Linn. 

 Hab. On the Sacramento, California; no doubt introduced. 



