panice^; 



83 



Panicam prostratum, Lamk. 



The plant is a slender annual and it consists of several branches, 

 prostrate and creeping, with adventitious roots at the nodes below, 

 branching or ascending above, all green or sometimes purple above 

 and green below, 4 to 18 inches long. 



The leaf-sheath is striate, I to 2 inches long, glabrous or very 

 sparsely hairy, purplish above and green below or all green, keeled, 

 margins ciliate on one side only throughout its length. The ligule 

 is a fringe of white hairs. The nodes are glabrous or pubescent. 



The leaf-blade is short or long, varying from % to 2% inches in 

 length and y\ to jV inch in breadth, convolute when young, 

 lanceolate to broadly ovate-lanceolate, acute or acuminate, upper 

 surface glabrous, and the lower glabrous or with a few scattered 

 tubercle-based hairs; margins are very minutely serrate ; base is 

 cordate, amplexicaul with a few long slender hairs (sometimes 

 tubercle-based), just close to the white patch on both sides on the 

 margin of the blade about the ligule. The midrib is distinct. 



The inflorescence consists of five to fifteen or twenty spikes 

 spreading in all directions, distant or crowded ; peduncle varies 

 from I to 4 inches. Spikes are Y 2 to iffc inches, sessile or shortly 

 stalked ; the rachis of the spike is slender, trigonous and scaberulous. 



Fig. 92. — Panicum prostratum. 

 A. Front and back view of spike ; B. front and back view of a spikelet ; i, 2, 3 and 

 4, the first, second, third and the fourth glume, respectively; 3a and 4a. the palea of 

 the third and the fourth glumes ; 5. anthers, ovary and lodicules. 



The spikelets are crowded all on one side, 2- to 3-seriate, ellip- 

 soidal, yo to "iV i ncn long, glabrous or pubescent, pale green or 

 purple on one side, in pairs on pedicels, one with a slightly longer 

 pedicel than the other; fine long hairs, varying in number from 

 one to eight and longer than th^ spikelets, are found on the pedicels 

 at their tips in some plants and not in others. 



There are four glumes in the spikelet. The first glume is very 

 short about V\ of the third or less, semilunar, membranous, hyaline, 

 subtruncate, obtuse or acute, generally nerveless, but rarely, 

 obscurely I- to 3-nerved. The second glume is membranous, ovate, 

 acute, glabrous or pubescent and 7-nerved. The third glume is of 

 about the same length as the second, 5-nerved, always paleate, with 



