181 



minate (one-fourth of an inch long), the green back faintly six- 

 nerved below ; the involute hjalino margins several lines wide, of a 

 dark-brown color, and slightly exceeding the inner sepals. Inner 

 sepals scarcely involute, acuminate, green on the back, faintly three- 

 nerved below, broadly hyaline-margined of a broAvn and white color. 



Ovary oblong ; style as long as the ovary ; stigmas three, long, 

 spirally twisted ; stamens six, on very short filaments (about one- 

 third the length of the anthers) ; pod obovate-triangular, abruptly 

 long-pointed, scarcely exceeding half the length of the outer sepals 

 (one-sixteenth of an inch in diameter) ; seeds oblong, smooth. 



Scape naked and simple, furnished below with leafless, obtuse 

 sheaths of a tawny color, terete, scarcely striate, l-o feet high. 

 One-fourth peduucled, corymbose and cymose panicles produced 

 from the side of the scape, at about 3—7 inches below the prni- 

 gent tip. 



Peduncles flat inside or triquetous, smooth 1-2 inches long (one 

 sometimes sessile^ ; each peduncle and pedicel subtended by two 

 taAvny, unequal, ovate-oblong, abruptly-pointed or obtuse, many- 

 nerved or nerveless bracts or scales. 



Flowers almost sessile, secund, subtended by two broadly-ovate, 

 obtuse or minutely-jiointed, tawny, hyalinous scales. 



Salt-marshes of the bay of San Francisco, October — November. 



Panicum thermale. — Spikelets two-flowered ; lower neuter, 

 upper hermaphrodite. Glumes two, very unequal, herbaceous, 

 pubescent ; lower very minute, ovate ; upper ovate, distinctly 5-7 

 nerved, acute. 



PalccTS of the neuter flower, two ; lower ovate-oblong, acute, five- 

 nerved, pubescent ; upper hyaline, one-half the size of the lower. 



PaleiTe of the hermaphrodite flower, ovate, cartilaginous, smooth, 

 lower enclosing partly the u})per. 



Ovary smooth ; styles terminal ; stigmas plumose ; stamens 

 three ; anthers purple ; squamulne two, smooth ; a low grass grow- 

 ing in large tufts ; roots fibrous ; culms (3-8 inches high, weak, com- 

 pressed, very branchy u})wards and leafy ; leaves short, flat, tliickish, 

 tomentose-pubescent, spiny-acuminate, very scabrous on the iiiar- 

 gins ; sheaths short, striate, peculiarly punctate ; ligula scarcely 

 visible, ciliate ; panicle very small, few-flowered, partly vaguiate, 

 shorter than the terminating leaves. 



The Avhole plant is like velvet to the feel. There are, however, 

 some specimens which are rather smooth. 



Habitat : On hot rocks and in hot water flowing from the Geyser 

 springs and Geyser mountauis, in the northern part of Sonoma 

 County. 



