HITCHCOCK AND CHASE—NORTH AMERICAN PANICUM. 283 
137. Panicum villosissimum Nash. 
Panicum tectum Willd.; Spreng. Syst. Veg. 1: 313.1825, This is given asa synonym 
under P. dichotomum. The type specimen, in the Willdenow Herbarium, is the 
autumnal form. It is labeled ‘‘Panicum tectum panicula divaricata. * * * 
Hab. a America boreali.’’ A second specimen so named in the Willdenow Herbarium 
was sent by Muhlenberg and is P. xalapense. 
Panicum dichotomum villosum Vasey, U.S. Dept. Agr. Div. Bot. Bull. 8: 31. 1889, 
not P. villosum Ell. 1816. The author cites “‘?. villosum Ell.?” but since on the same 
page he gives this name unquestioned as a synonym of 1’. consanguineum Kunth, 
Elliott’s species can not be taken as the basis of Vasey’s variety. No locality nor speci- 
men iscited. A freely branching early autumnal specimen in the National Herbarium 
marked ‘“‘dichotomum var. villosum” in Vasey’s writing, and agreeing well with his 
description, is chosen as the type. This was collected “near Pierce’s Mill, Rock 
Creek, D. C., July 1, 1883,’ by Dr. Vasey. 
Panicum nitidum pubescens Scribn. in Kearney, Bull. Torrey Club 20: 479. 1893. 
This is listed without description as the name of two numbers, 58 and 141, of Kearney’s 
collection of plants in Harlan and Bell Counties, Kentucky. “Panicum laxiflorum 
pubescens Chapm.”’ is cited but as the latter name had not at that time been published 
by Chapman, P. nitidum pubescens must be considered a nomen nudum. The speci- 
mens of his 58 and 141 in the National Herbarium, and distributed by Kearney, com- 
prise P. villosissimum and P. huachucae, but the majority are the former. 
Panicum laviflorum pubescens Chapm.; Kearney, Bull. Torrey Club 20: 479, 1893, 
not Vasey 1892, This is given asasynonym of 2’. nitidum pubescens Scribn., but is later 
described by Chapman@ and based on P. pubescens Lam, 
Panicum villosissimum Nash, Bull. Torrey Club 23: 149, 1896. ‘Collected by Dr. 
John K. Small in the Ocmulgee River swamp, below Macon [Georgia], May 18-24, 
1895.’ The type, in Nash’s herbarium, consists of several vernal culms with branches 
appearing, but secondary panicles not expanded, The spikelets are 2.5 mm. long. 
Panicum atlanticum Nash, Bull. Torrey Club 24: 346, 1897. ‘“‘Type specimens 
collected by the writer on dry somewhat shaded knolls in the grounds of the New York 
Botanical Garden.’”? The type, in Nash’s herbarium, consists of a small clump and of 
two single specimens, the culms beginning to branch, primary panicles mature, sec- 
ondary panicles immature. The spikelets are 2.2 mm. long. This differs from the 
type of P, villosissimum only in the somewhat stiffer culms and slightly smaller 
spikelets. , 
Panicum haemacarpon Ashe, Journ, Elisha Mitchell Soc, 15:55, 1898, ‘‘ District 
of Columbia: Kearney; 1897. Ashe: North Carolina; Chapel Hill, 1898. Towa: 
Carver; Jewell Junction, 1895, No, 258.’ The first specimen cited is chosen as the 
type. This is in Ashe’s herbarium and consists of a tuft of three simple culms with 
nearly mature panicles and two autumnal culms of the previous year, 
Panicum xanthospermum Scribn. & Mohr, Contr. Nat. Herb, 6: 348. 1901. “‘Type 
specimen collected by Dr. Charles Mohr in open sandy soil, Greenville, Butler County, 
Ala., May 8, 1898.”’ This specimen, which is in the National Herbarium, consists of a 
tuft with two simple culms 18 and 20 cm. high, and the burned bases of others, evi- 
dently a second growth after a fire. Except in its smaller size it compares well with 
the type of P. atlanticum. The spikelets, which are immature, are 2.2 mm. long. 
By selecting the shorter culms it could be matched from many typical clumps of P. 
villosissimum. 
This species was described by Scribner? as Panicum pubescens Lam., as indicated 
by a note upon a sheet, then in his possession, of a duplicate type of P. villosissimum. 
a}l. South. U. 8. ed. 3. 586. 1897. 
b Tenn. Agr. Exp. Sta. Bull. 7:52. pl. 15. f. 58. 1894. 
