TRIANDRIA. DIGTNIA, 53 



have the valves of the calix approaching to equality," 

 mostly acuminated; in these there is generally, if not 

 constantly, an innperfect floret producing stamens, and 

 they are usually furnislied with a dichotomous pani- 

 cle, either appressed, or diffuse and pyramidal.-f- 



The generic character of Panicum is now described by 

 Schreber as follows: 



Calix of 2 very unequal valves, containing 2 flowers, 

 the outer one male or neuter Corolla of 2 unequal valves, 

 finally cartilaginous and investing the seed. 



Schreber remarks, that the inner glume of the imper- 

 fect flower being overlooked, its outer glume was con- 

 ceived to belong to the calix: hence the calix was thought 

 to consist of 3* valves, of which the third was much tlie 

 least. 



Species. .§ i. Paniculate; flowers in dense racemes. 

 — 1. Crus.galli. 2- Walteri. 3. gibbim, El. 4. imlle, (calix 

 only 2-valved? but 2-flowered, one of the flowers stam- 

 niferous only, allied to Milium? Mich.) 5. gijnmocarpon, 

 El. (a very remarkable species, with the valves of the 

 calix somewhat carinated, and nearly all equal, with an 

 imperfect neutral rudiment attached to the base of tlie 

 perfect flower; the wl.itish indurated corolla in seed al- 

 most resembles a Scleria, and is scarcely half the length 

 of the calix. This species is closely allied to the genus 

 Orthopogon oi" Bvo\yn,hu.t the valves are only acuminated, 

 not awned ) d. genicidatum, El. 7- anceps 8. hians, El. 

 (P. dixaricatinn. Mich.) 9.fiisco-rxibens.—§ ii. Mowers in 

 panicles. — 10. virgatum. 11. ?utidum l2. dichoiomum. 13. 

 capillare. 14. latifoliwn. iS.scopari'um. 16. pmicijloriimy E,u. 

 17. mnaruyn, (of an extremely bitter taste! El.) 18 scabrius^' 

 cuhim 19. nervosum, E. 20. midtiflorum, E. 21. ovcdcy E. 

 22. lanuginosum, E. 23. viscidum, E. (remarkably viscid 

 or glutinous near the nodes of the culm. Several other 

 species in the United States have glandular exudations.) 

 24. villo&vm. El. 25. pubescens. 26. splucrocarpon, E. 2T- 

 ciUatum, E. 28. ensifoUinn, E. 29 barbidaUmi. 30. microcar- 

 pon, E. 31. JMelicarhnn. 32. debile, E. 33. angustifoUum. 

 34. divergens, E. 2>5. elongatum, Pursh. 



The south-.' rn and middle states of North America 

 now afford about one third as mnny species of this ge- 

 nus as are at present discovered in the world. About 110 

 genuine species of Panicum are described, independent 

 of those with involucellate spikes, v.iiich are now placed 

 in the genus Pennisetwn, and a few others in Orthopogon. 



t This habitus merely describes the American sDecles. 

 ± 2 



