18 NORTH AMEBIC AT* SPECIES OF LEPTOCHLOA. 



Leptochloa polystachya Kunth. Rev. Gram. 1: 91. 1835 (or earlier?). Transfers 

 Michaux's Festuca polystachya. Under the rule once a synonym always a 

 synonym the Australian species should receive another name (Leptochloa 

 polystachya Benth. Fl. Austr. 7: 617. 1878). Bentham says (p. 618), "I 

 have been able to retain Brown's specific name, as the American Diplachne 

 panicularis [fascicidaris] named Leptochloa polystachya by Kunth is gener- 

 ally retained under the former genus. Syn. Cynodon polystachya R. Br. Prod. 

 187. C. virgatus Nees in Steud. Syn. 1 : 213. C. Neesii Thw. Enum. PL Ceyl. 

 371." 



Diplachne acuminata Nash in Britton Man. 128. 1901. Represented from 

 Nebraska, Rydberg 1713; Arkansas, Coville 87; Colorado, Clements 263. 



TJralepsis composita Buckley. Proc. Acad. Phil. 1862: 94. 1863. "New Mexico. 

 Dr. Woodhouse." I have examined this specimen in the herbarium of the 

 the Academy. 



Diplachne tracyi Vasey. Bull. Torr. Bot. Club. 15: 40. 1888. "In clumps 

 growing in ditches at Reno, Nevada." Tracy No. 216. Dr. Vasey remarks 

 that this is " Near D. fascicularis." In the type specimen which is in the 

 herbarium of the Department of Agriculture the lateral nerves are more con- 

 spicuously excurrent than is usual in D. fascicidaris. but there seem to be no 

 constant characters by which this form can be separated. It is a large form, 

 with more exserted panicles, found from Nevada to Mexico, Pringle 813; 

 Palmer 691. 



Leptochloa tracyi Beal. Grasses N. A. 2: 436. 1896. Transfers Diplachne tracyi. 



Festuca midtiflora Walt. Fl. Car. 81. 1788. 



" Repens, paniculis erectis ovatis, spiculis 8 ad 40-fl.oris acutis, floris angustis, 

 acutis, fauce subplumosis." This may refer to L. fascicidaris, but the 

 description is scarcely sufficient. This plant is not represented in Walter's 

 herbarium, which is at the British Museum. 



Stems tufted, smooth. 3 to 12 dm. high, erect or procumbent. Leaves narrow, 

 usually involute, 1 to 3 dm. long, 3 to 5 mm. wide; sheaths smooth or slightly 

 scabrous. Panicles from a few cm. to 2 dm. long, more or less included in 

 the upper sheath; branches of panicle few or several and of variable length, 

 in the larger forms as much as 1 dm., appressed or ascending, or at maturity 

 spreading. Spikelets usually somewhat overlapping, 7 to 12 mm. long, 6 to 

 12 flowered. Empty glumes narrow, acute, lower 2 to 3 mm. long, about 

 one-half the upper; flowering glumes 4 to 5 mm. long, with an awn of variable 

 length, sometimes, especially in the procumbent form, as long as the glume; 

 lateral nerves pubescent below. 



Distribution: Maryland to Florida and west to South Dakota and New Mexico. 

 Texas: Jones 4203; Drummond 387. Kansas: Hitchcock 920. Florida: Nash 

 2306. St.Cro ix . ■ Ricksecker 306. Cuba: Wright 3822, 3812. Mexico : Pringle 

 813; Palmer 254, 691; Schaffner 683 (D. procumbens). 



LEPTOCHLOA IMBRICATA Thurb. Bot. Calif . 2 : 293. 1880. " Larkins 

 Station, San Diego County (Palmer No. 404); Fort Yuma (Major Thomas); 

 and through the Gila Valley to the Rio Grande. ' ' (PI. V, fig. 2; text fig. 14. ) 



Diplachne imbricata Scribn. inTasey 111. N. A. Grasses l 2 : No. 42. 1891. Trans- 

 fers Leptochloa imbricata and gives a plate. 



Diplachne verticillata Nees&Mey. Nov. Act. Nat. Cur. 19. Suppl. 1 : 158. 1843. 

 (Not Leptochloa verticillata Kunth, 1835. ) "Ad Copiapo in republica Chilensi, 

 Martiol831,et ad Aricam Peruviae." The authors remark that this species 

 differs from Diplachne virens of Brazil (presumably Tridens virens Nees) 

 and D. fascicidaris in having the glumes not awned from the apex but very 

 shortly mucronate and from the first in its larger spikelets. I have examined 

 T. virens Nees and think it is not identical with L. imbricata Thurb. 



