OF MAEINE COASTS. 91 



Hippuris vulgaris L. f. maritima. 



Perennial rootstock, with annual stems, 3 — 6 dm. high, stout; leaves 

 entire, linear, acute, 10 — 15 mm. long; flowers inconspicuous. 



Occurs on coasts of Baltic. The typical form is dispersed over 

 Europe and northern Forth America, and is not a coast plant. 



RHIZOPHOREAE. 

 Rhizophora mangle L. 

 The common mangrove of all tropical coasts does not, as a rule, 

 occur on sandy shores, but occasional specimens can be found on sandy 

 beaches or fringing sandy islands. 



MTRTACEAE. 

 Galythrix aurea Lindl. 

 Erect shrub, rigid, not much branched, minutely pubescent; leaves 

 erect, ovate, thick, concave, obtuse, ciliate on margins and midrib, 

 flowers yellow in leafy heads. 



Together with other species of the same genus on sands at Swan 

 Eiver, West Australia. 



Kunzea pomifera E. Muell. 



Eigid, prostrate shrub, glabrous, or young shoots somewhat pubescent; 

 leaves ovate, narrow at base, rigid, spreading, obtuse, 6 — 12 mm. long; 

 flowers white. 



Sandy shores of Victoria and South Australia (St. Vincent's Gulf). 

 Also in interior deserts of Australia. 



Leptospermum laevigatum E. Muell. 



Tall shrub, glabrous, somewhat glaucous, young shoots often silky; 

 leaves oblong, 1 — 4 cm. long, 3-nerved, alternate, rigid, entire; flowers 

 white. 



Coastal sand formations in Australia (Sydney, Port Phillip, South 

 Australia, and Tasmania). Does not extend to West Australia. 



L. scopwrium Eorst. 



Eigid shrub to 7 m. high tree, much-branched; leaves small, ovate, 

 alternate, erect, concave; young shoots covered with silky hairs, adult 

 foliage mostly glabrous. 



Australia and New Zealand on the beach. In the latter country it 

 extends to an altitude of 1000 m. 



