188 



Chxise — Notes on Genera of Paniceae. I. 



Field Col. Mus. Bot. 3 : 28) transfer T.insularis to Syntherismn, remarking : 

 " That this species belongs in the genus Syntherisma rather 

 than in Panicum is shown chiefly by the fruiting glumes 

 which are of the form characteristic of the former, having 

 a floral glum*.* with hyaline margins not inrolled." 



Description. — Spikelets in pairs, short-pediceled in 2 rows 

 along one side of a narrow rachis, the slender racemes 

 erect or nearly so, solitary' or fascicled along a common 

 axis forming a narrow panicle; spikelets lanceolate, first 

 glume minute, glabrous, the second and sterile lemma us- 

 ually as long as the fruit or longer, 3-5 nerved, copiously 

 clothed with long silky hairs (in one species, only, the 

 silky hairs are not long and dense) ; fruit lanceolate, usual- 

 ly brown, the flat, white, hyaline margins broad; grain 

 ellipsoid, in section unequally biconvex. 



This genus is very closely allied to Si/ntherisma Walt. 

 One species, Fanicuin FiUieri Hack., has the inflorescence 

 of Vulota, but the hairs on the second glume and sterile 

 lemma are not long and copious, and the second glume 

 is shorter than the fertile lemma as in some SyntJierismas. 



But considering the diverse aspect of the two genera as a whole it seems 



wisest to regard them as distinct. 



The following species are transferred to this genus : 



Valota insularis (L.) 



Androporjon iitanlure L. 1859. Pugill. Jam. 30. 

 Valota saccharatum (Buckl.) 



Panicum lachnanthum Torr. 1850. Pac. Rail. Rep. 7 ^ : 21, not Hochst. 



1855. 

 Panicum saccharatum Buckl. 1866. Prel. Rep. Geol. & Agr. Surv. Tex. 



App. 2. " Middle Texas." 

 Trichachne saccharatum (Buckl.) Nash. 1903 in Small Fl. So. U. S. 83. 

 Valota Pittieri (Hack.) 



Panicum Pitlieri Hack. 1901. Oest. Bot. Zeitsc. 51 : 367. "Costarica: in 

 ripa rivi Rio Tirili prope San Jose leg. Tonduz: Pittier distribuitsub 

 nro. 6945." 

 The species represented in American herbaria by Nealley's Texas collec- 

 tions and passing under the name I'anicum ienerrimum Kunth, (based on 

 Trichachne tenuis Nees) does not well agree with Nees' description. Since 

 authentic specimens of this and Nees' other Brazilian species have not yet 

 been seen, his species and the Texas form are left for future study ; and to 

 avoid the possibility of making unnecessary combinations by taking up 

 possible synonyms these species and an Australian one with stramineous 

 fruits are not here transferred to this genus. 



Genus SYNTHERISMA Walt. 1788. Fl. Carol. 76. 

 Digitaria Haller 1768. Stirp. Helv. 2 : 244 not Adans. 1763, nor Heist. 

 1759, though Haller gives Heister and Adanson as authors of his Digitaria; 

 but his description, though he evidently makes an effort to harmonize it 



