1912] Hubbard,— Nomenclatorial Changes in Gramineae 167 
PANICUM HEMITOMUM Schultes. 
Under this species in Hitchcock and Chase Contr. Nat. Herb. 16 : 
322 (1910) ! the first synonym is P. Walteri Ell. Sk. Bot. S. C. & Ga. 1: 
115 (1816). Schultes Mant. 2: 227 (1824), bases his species, P. 
hemitomum on P. Walteri Muhl. Descr. Gram. 108 (1817); this is the 
second synonym given by Hitchcock and Chase l. c. 323. P. Walteri 
Muhl. was probably described from Elliott's plant, as the specimen 
in the Muhlenberg Herbarium is labeled “Panicum dimidiatum 
Walter, Ell. 478” and is evidently a duplicate of Elliott's plant [cf. 
Hitche. & Chase l. c. 323]. Both Elliott and Muhlenberg cite P. 
dimidiatum Walt. Fl. Carol. 72 (1788), as a synonym of their species 
[in fact the herbarium specimens of both are labeled P. dimidiatum 
Walt.— cf. Scribn. U. S. Div. Agrost. Cire. 29: 4 (1901) and Scribn. 
& Merr. U. S. Div. Agrost. Circ. 27: 2 (1900). The name dimidiatum 
antedates all others applied to the species, but it is not advisable to 
use it because unquestionably it is a misapplication of P. dimidiatum 
L. Sp. Pl. 57 (1753) and not intended as a new species. P. dimidiatum 
L. equals Stenotaphrum dimidiatum (L.) Brogn. in Duperry Voy. Coq. 
Bot. 127 (1828) [cf. Hitche. Contr. Nat. Herb. 12: 116 (1908) under 
discussion of P. dissectum L.]. 
P. Walteri Ell. is well described and the type specimen is known. 
However, the specific name Walteri, of Elliott, is antedated by P. 
Walteri Pursh Fl. 1: 66 (1814) and P. Walteri Poir. in Lam. Dict. 
Suppl. 4: 282 (1816) and is consequently invalid according to the 
American Code. P. Walteri Pursh |. c. from the description is evi- 
dently a species of Echinochloa and is given by Torrey Fl. N. Y. 2: 
424 (1843), as a synonym of Echinochloa crusgalli (L.) Beauv. P. 
Walteri Poir. 1. c. equals P. Boscii Poir. in Lam. Dict. Suppl. 4 : 278 
(1816) [cf. Hitche. & Chase l. c. 317]. Since the older P. Walteri 
Pursh and P. Walteri Poir. are invalid, they do not invalidate P. 
Walteri Ell. (Sect. 7, Art. 50 of the * Vienna Code"), and consequently 
the valid name of what has been known as P. hemitomum Schultes is 
P. Walteri Ell. 
Panicum WALTERI Ell. Sk. Bot. S. C. & Ga. 1:115 (1816), not Pursh 
l. c. (1814) nor Poir. l. c. (1816). Synonymy in part: P. hemitomum 
Schultes Mant. 2: 227 (1824); Hitche. in Gray Man. ed. 7, 103 
1I have cited Hitchcock & Chase North American Species of Panicum under the 
serial title Contr. Nat. Herb. 18 throughout this article. 
