42 Proceedings of the Biological Society of Washington. 



upper 2 cm. broad; panicle narrowly oblong, erect or a little nodding 

 near the top, 15 to 40 cm. long ; branches slender, ascending, the longest 

 about half the length of the panicle, all naked toward the base ; lower 

 glume of fertile spikelet coriaceous, ovate, very convex, constricted at 

 base, nerved near the tip, smooth and shiny on the back, hairy at base 

 and on the margins, straw-colored but apparently becoming reddish at 

 maturity, 4-5 mm. long, 2-2.5 mm. broad, faintly 7-nerved ; awns 10-12 

 mm. long, or in one panicle wanting; sterile spikelets very narrow, 

 longer than their hairy pedicels. The sterile spikelets drop early but the 

 fertile are persistent, apparently as much so as in cultivated forms. 



Banks of White Nile a little south of Gaba Shambe, intermingling with 

 other grasses but much taller. Consul Petherick, June 25, 1862 (Kew). 



This subspecies is clearly allied to cordofanua, but differs in its larger 

 looser panicles and smaller spikelets. 



What may be the same subspecies has been collected on Ruwenzori by 

 O. F. Scott Elliott No. 7612 (Kew). The specimen is slender about 60 

 cm. high, with leaves 1 cm. broad, and a somewhat secund panicle 16 cm. 

 long. The spikelets are orange-red but very similar in form to the 

 Petherick specimen. 



Andropogon sorghum drummondii (Nees) Hackel. 



Andropogon drummondii Nees; Steudel Syn. PI. Glum. 1:393. 1854. 

 Andropogon sorghum drummondii Hackel in DC. Monogr. Phan. 6:507. 

 1889. 



Culms al)Out 2 meters tall, commonly solitary or but few from the 

 same root, stout, often 1 cm. or more in diameter; leaf blades pale, fiat, 

 the upper 2 to 4 cm. broad, 40 to 50 cm. long; panicle pyramidal-oblong, 

 erect, commonly 30-40 cm. long, rather dense; branches ascending, the 

 lower about one-fourth the length of the panicle, naked at base ; lower 

 glume of fertile spikelet elliptic to ovate-elliptic, very coriaceous, nerved 

 for the upper third, distinctly constricted at base, 5-6 mm. long, 2-2.5 

 mm. broad, 11-nerved, glabrous on the back, sparsely pubescent near 

 the margins, persistent, straw-colored but often becoming reddish at 

 maturity; sterile spikelets narrow, about 3 mm. long on hairy pedicels 

 of about the same length; grain oval, flattened, 4 mm. long, orange- 

 colored. 



This subspecies was originally described from specimens collected by 

 Drummond at New Orleans in 1832. Those preserved at Kew are very 

 young small plants with the panicle just emerging. In Louisiana and 

 Mississippi this plant has long been known as "chicken-corn," it ap- 

 pearing spontaneously each year in cultivated ground. In recent years 

 it has become scarce due probably to the work of the sorghum midge. 

 Chicken corn is very similar to cultivated varieties of sorghum. The 

 stems contain no f^ugar. The constriction at the base of the fertile spike- 

 let is a very constant character, but occurs in some other wild sorghums. 



Chicken-corn was undoubtedly brought to America by negro slaves, 

 perhaps accidentally. African specimens have been examined as follows: 



