438 



ELATINACEAE. 



[VOL. II. 



2. Elatine brachysperma A. Gray. Short-seeded Water- wort. (Fig. 2467.) 

 Elating brachysperma A. Gray, Proc. Am. Acad. 13: 361. 1878. 



Terrestrial or sometimes submerged, spreading, tufted, i / -2 / long. 

 Leaves oblong, oval or lanceolate, narrowed at the base, 2 // -3 // long, 

 about \" wide, obtuse; flowers sessile, axillary, minute; sepals, pet- 

 als, stamens and stigmas mainly 2; capsule nearly as in the preceding 

 species; seeds short-oblong, nearly straight, about %" long, marked 

 by 6-7 longitudinal striae and 10-12 cross-bars. 



Margins of ponds, Illinois and California, doubtless occurring between 

 these limits. Summer. 



3. Elatine triandra Schk. Long- stemmed 

 Water- wort. (Fig. 2468.) 



Elatine triandra Schk. Bot. Hand, x: 345. 1791. 



Flaccid, tufted, immersed or creeping, stems 

 2'-4 x long, much branched. Leaves oblong or ob- 

 lanceolate, very thin, obtuse, 2"-4 // long, i" 

 wide, narrowed at the base; flowers minute, axil- 

 lary, sessile; sepals commonly 2; petals, stamens 

 and stigmas 3; seeds slightly curved, about the 

 size of those of E. Americana, slightly marked 

 longitudinally and transversely. 



Ponds, Illinois and Nebraska. 

 Summer. 



Also in Europe. 



2. BERGIA L. Mant. i: 152. 1771. 



Herbs, or somewhat shrubby plants, branching, erect, ascending or prostrate, more or 

 less pubescent, with opposite serrate or entire leaves, and small axillary solitary or clustered 

 flowers. Parts of the flower in 5's (very rarely in 4's or 3*3). Sepals acute. Pod crustaceous, 

 ovoid, 5-valved. Seeds numerous, striate longitudinally and transversely. [In honor of Dr. 

 P. J. Bergius, 1723-1790, professor of Natural History in Stockholm.] 



About 15 species, natives of warm and temperate regions. 



i. Bergia Texana (Hook.) Seub. Texas Bergia. 

 (Fig. 2469.) 



Aferimea Texana Hook. Icon. PI. pi. 278. 1840. 

 Bergia Texana Seub.; Walp. Rep. x: 285. 1842. 



Prostrate or ascending, diffusely branched, pubescent, stems 

 6 / -io / long. Leaves spatulate or obovate, i'-ij' long, 6"- 

 8" wide, acutish or obtuse, serrate, narrowed into a short 

 petiole; stipules scarious, about i" long, ciliate-serrulate; 

 flowers short-peduncled, about i Y^" broad, solitary or 2-3 to- 

 gether in the axils; sepals ovate, acuminate, denticulate, 

 slightly longer than the oblong obtuse petals; capsule glo- 

 bose, i" in diameter, its dehiscence septifragal; seeds oblong, 

 striate longitudinally and cross-barred. 



Southern Illinois to Texas, west to Nevada and California. 

 Summer. 



