78 



CONTRIBUTIONS FKOM THE NATIONAL HEKBARIUM. 



Panicum bergii Arechav. a a South American species with numerous leaves 

 clustered at the base, hispid sheaths, involute blades, and very diffuse panicles, a 

 third or more the entire height of the plant, with verticillate lower branches, 

 conspicuously pilose in the axils, and short-pointed spikelets 2.2 to 2.6 mm. long, 

 was collected on ballast at Mobile, Alabama, in July and August, 1891, by Mohr and 

 at Galveston, Texas, in 1903, by Hitchcock (the latter in Hitchcock Herb.). 



Maxima. — Perennials; culms mostly robust and more than 1 meter high, simple or 

 branching at the base only, or with small sterile shoots from the lower nodes; 

 ligules membranaceous, ciliate; blades linear, flat; panicles large, many- 

 flowered; spikelets ellipsoid, glabrous, mostly faintly nerved, the sterile 

 floret with a well-developed palea and in P. maximum a staminate flower; 

 fruit strongly to very obscurely transversely rugose, puberulent at the apex. 

 Culms with a corm-like base. 



Blades mostly over 5 mm. wide; culms more than 1 



meter high 41. P. bulbosum. 



Blades less than 5 mm. wide; culms rarely as much as 1 



meter high 41a. P. bulbosum sci- 



aphilum. 

 Culms from a creeping rootstock, not corm-like at base. 



Nodes hirsute; ligules 4 to 6 mm. long; fruit strongly 



rugose ' 39. P. maximum. 



Nodes glabrous; ligules 2 mm. long; fruit very obscurely 



rugose 40. P. plenum. 



„ 39. Panicum maximum Jacq. 



Panicum maximum Jacq. Coll. Bot. 1: 76. 1786. "In insula Guadeloupe sponte 

 crescit." In the Vienna Herbarium is a specimen from "Hb. Jacq. fil."& This is 



probably the most authentic specimen to be obtained. 

 The plate in Jacquin's Icones c is an excellent illus- 

 tration of the species as commonly understood. 



Panicum polygamum Swartz, Prodr. Veg. Ind. 

 Occ. 24. 1788. "India occidentalism is the only local- 

 ity cited. The type specimen, marked "Jamaica. 

 Swartz. P. polygamum prodr.," is in the Swartz 

 Herbarium. 



Panicum laeve Lam. Tabl. Encycl. 1 : 172. 1791. 

 "E Domingo, ins. Franc." is the only citation given. 

 The type specimen, in the Lamarck Herbarium, is 

 marked ' 'Panicum laeve n. Lam. ill. gen. * * * 

 Ste. Dominique." 

 Panicum jumentorum Pers. Syn. PI. 1 : 83. 1805. 

 Based on P. polygamum Swartz, the description of which Persoon copies. 



Panicum scaberrimum Lag. Gen. & Sp. Nov. 2. 1816. "Habitat in Nova Hispania. 

 Introd. ann. 1804 ex seminibus per. D. Sesse missis." The type specimen, in the 

 Madrid Herbarium, bears a label reading "Panicum scaberrimum sp. n. Ex h. r. m.d 

 an 1804. Habitat in N. Hispania." 



a Anal. Mus. Nac. Montevideo 1: 147. 1894. "Campos del Departmento de Monte- 

 video, San Jose, Florida, Mercedes, etc." 



b Nicolas Joseph Jacquin the author of the Collectiones. 



c Icon. PL Par. 1 : 2. pi. 13. 1781-1786. This work is dated 1781-1786, but "Jacq. 

 coll. vol. 1" is cited, which would indicate that the Collectiones appeared the earlier. 



d Hortus regius Matritensis. 



Fig. 67. — P. maximum. From type 

 specimen of P. polygamum Swartz. 



