HITCHCOCK AND CHASE — NOKTH AMERICAN PANICUM. 



175 



Fig. 168. — P. ovinum. From type 

 specimen. 



most ovate or lanceolate, as much as 1 cm. wide, those of the mid-culm, 10 to 15 cm. 

 long, 3 to 6 mm. wide, the uppermost shorter and narrower; panicles usually short- 



exserted, 5 to 9 cm. long, three-fourths as wide or 

 less, loosely flowered, the lower branches ascend- 

 ing; spikelets 2.1 to 2.2 mm. long, 1.2 to 1.3 mm. 

 wide, obovate-elliptic, obtuse, basal attenuation 

 short; first glume about one-fourth the length of the 

 spikelet, usually truncate; second glume and sterile 

 lemma scarcely equaling the fruit at maturity, 

 papillose-pubescent, sometimes minutely so; fruit 

 1.8 mm. long, 1.1 mm. wide, oval, puberulent at 

 the apex. 



Autumnal form erect or nearly so, the blades 

 becoming loosely involute, not much shorter than the vernal blades; spikelets more 

 turgid, sometimes slightly shorter than those of the primary panicle. 



Panicum ovinum in its vernal form differs from P. adculare in being nearly smooth, 

 and in having broader spikelets and 

 larger, less exserted panicles, the upper- 

 most blades being proportionately 

 longer. 



DISTRIBUTION. 



Dry or moist open ground, Missis- 

 sippi to Arkansas and eastern Texas; 

 also in Mexico. In Texas this species 

 occurs upon the open prairie, on dry 

 ground, and also in swales. 



Mississippi: Ocean Springs, Tracy 

 4616 in part; Biloxi, Hitchcock 

 1077-1. 

 Arkansas: Jefferson County, Eggert in 1898 (Mo. Bot. Gard. Herb.). 

 Louisiana: Shreveport, Hitchcock 1250; Lake Charles, Hitchcock 1131, 1141, 1150. 

 Texas: Dallas, Reverchon 1087; Waller County, Hitchcock 1172, 1192, 1210, 1222, 

 Thuroiu in 1898 and 1906; Montgomery County, Thurow in 1905; Grand 

 Saline, Reverchon 4137 ; Hempstead, flaZZ 834 (Gray Herb.); without locality, 

 Nealley in 1884 and 1887, Reverchon 92 in 1879. 

 Mexico: Hacienda de la Laguna, near Jalapa, Schiede (Berlin Herb.). 



1 98. Panicum neuranthum Griseb. 



Panicum neuranthum Griseb. Cat. PL Cub. 232. 1866. "Cuba or. (Wr[ight] 3453); 

 occ, in savanis pr. Hanabana (Wr[ight] a. 1865: forma ascendens, ramosa, foliis 

 planis, spiculis ut in a)." The type specimen, in the Grisebach Herbarium, was 

 collected by Charles Wright in eastern Cuba in 1860 and is numbered "103=3453." 

 This is the autumnal form. Another specimen, the second one cited above, was col- 

 lected in 1865 and is labeled "a forma ascendens ramosa." This specimen is P. 

 chrysopsidifolium. « 



description. 



Fig. 169.— Distribution of P. ovinum. 



Vernal form with numerous cespitose, stiff, erect, glabrous culms, 30 to 60 cm. high; 

 sheaths glabrous or ciliate on the margin and usually with a few long hairs at the 

 summit, or the lowermost sparsely ascending-pubescent; blades erect or ascending, 



a See Hitchcock, Contr. Nat. Herb. 12: 183. 1909, for a discussion of Wright's Cuba 

 grasses. 



