80 THE SAND STRAND FLOBA 



It is especially a maritime form, 8. maritima Don., with thicker 

 leaves, which occurs on the coast. Europe, Central Asia, North America, 

 Australia. 



Silme gallica L. 



Annual herb, hairy, viscid, 15 — 35 cm. high, erect; lower leaves 

 small, obovate, the upper ones narrow and pointed, flowers small, white. 



Common on sand, gravel and waste places in almost every part of 

 the world, and seems to prefer the coast. Abundant on dunes at Fre- 

 mantle, West Australia, and in Central California. 



S. nicaeensis All. 



Perennial herb, covered with long viscid hairs; leaves green, linear- 

 oblong, obtuse, acute. 



Coastal sands of Mediterranean countries. 



Of this genus several species as 8. viscosa Pers., 8. maritima With., 

 and 8. inflata Sm. var. litoralis are distinctly maritime near the Baltic, 

 but usually do not occur on sand. 



Tissa Clevelandi Greene. 

 Perennial, viscid, glandular; stems prostrate, forming deep-green 

 mats, 10 — 30 cm. broad; leaves filiform, conspicuously fascicled in the 

 axils, all longer than the internodes. 



On the dunes near San Francisco, Presidio near that city being the 

 type locality. 



T. macrotheca (Hornem.) Britt. 



Perennial herb, succulent with fusiform fleshy roots, stout stems, 

 18 — 30 cm. high, erect or ascending from the short, often branched, 

 woody crown of the thick taproot; herbage deep green, viscid-pubescent 

 above, glabrous below; leaves narrow-linear, 2 — 4 cm. long; stipules 

 large, ovate. 



Common on sands near San Francisco and Pacific Grove, California. 



Var. scariosa Britton, with paler herbage, glandular-pubescent, or 

 almost glabrous, and short internodes, is frequently met with on dunes 

 at San Francisco and Monterey, although it prefers the bluffs near sea. 



T. marina (L.) Britton. 

 Annual, biennial, or mostly perennial herb, glabrous or with short 

 viscid pubescence; numerous stems branching from base, forming pros- 

 irate tufts, 6 — 12 cm. long; leaves fleshy, on coast, linear, with small, 

 scarious stipules at base; flowers pink or white. 



