1912] Hubbard,— Nomenclatorial Changes in Gramineae. 173 
Panicum AsHEI Pearson. 
P. Ashei Pearson in Ashe Journ. Elisha Mitchell Soc. 15 : 35 (1898) 
is antedated by P. umbrosum LeConte in Torr. Cat. Pl. N. Y. 91 (1819). 
P. umbrosum Le Conte is given as a synonym of P. Ashei Pearson by 
Hitchcock and Chase Contr. Nat. Herb. 15 : 301 (1910) and is repre- 
sented by specimens in the Torrey Herbarium, according to Hitch- 
cock and Chase l. c., who point out that, while the sheet also contains 
a piece of a culm of P. dichotomum L., Le Conte's description (though 
not applying in all respects) applies better to the two vernal culms. 
These two vernal culms are what is know as P. Ashei Pearson. 
Retzius [Obs. 4 : 16 (1786)] describes a plant as P. umbrosum which 
usage of wmbrosum antedates P. wmbrosum Le Conte (1819). The 
Retzius species is, however, given by various authors as a synonym 
of P. prostratum Lam. 'Tabl. Encycl. 1:171 (1791) which equals P. 
reptans L. Syst. Nat. ed. 10, 2:870 (1759) [cf. Hitche. & Chase l. c. 
36 (1910)]. Lamarck l. c. under P. prostratum cites P. umbrosum 
Retz. as a synonym. Nees, Agrost. Bras. 109 (1829) cites it as a 
synonym under P. procumbens Lam. [As Lamarck apparently did 
not describe any species under the name of procumbens, it is probable 
that Nees intended to treat P. prostratum Lam. especially so as he 
cites the Lamarck varieties of P. prostratum]. Hooker f. [Fl. Brit. 
Ind. 7 : 34 (1896)] cites P. wmbrosum Retz. in a note under P. prostra- 
tum Lam. saying that he (Hooker f.) cannot untangle the synonymy of 
P. prostratum Lam. and P. villosum Lam., but seems to lay stress on the 
synonymy as given by Nees. 
As there has been no disposition on the part of any writer from the 
time of Lamarck (1791) to Hooker f. (1896) to treat P. wmbrosum 
Retz. as a valid species it would seem advisable to accept the general 
belief that it is a synonym of P. reptans L. (P. prostratum Lam.), 
in which case (according to Sect. 7, Art. 50 of the “Vienna Code") 
the valid name of P. Ashei Pearson is P. umbrosum Le Conte. Accord- 
ing to the American Code P. Ashe? Pearson remains valid. 
PANICUM UMBROSUM Le Conte in Torr. Cat. Pl. N. Y. 91 (1819) not 
Retz. |. e. (1786). P. Ashei Pearson in Ashe Journ. Elisha Mitchell 
Soc. 15 : 35 (1898); Hitche. in Gray Man. ed. 7, 113 (1908); Hitche. & 
Chase Contr. Nat. Herb. 15 : 301 (1910). 
(To be concluded.) 
