ALASSIO AND ITS FLORA 
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Polygonum litorale, Lk. — Nat. Ord. 
Polygonaceae. 
July, August. 
Polygonum maritimum, L. — Nat. Ord. 
Polygonaceae. 
Almost all the year. 
Populus alba, L. — Nat. Ord. Saliceae. 
In some torrents, and in gardens, as 
an ornamental tree. 
February. 
Portulaca oleracea, L. — Nat. Ord. Por- 
tulaceae. Vulgo Porcellana.' 
Almost all the year. 
Posidonia caulina, KoN. — Nat. Ord. 
, Naiadaceae. Syn. Zostera oceanica, L.; 
Posidonia oceanica, Del. 
Bears fruit in March and April; it 
forms large cloump on the bottom of 
the sea. 
October. 
Potamogeton pusillus, L. — Nat. Ord. 
Najadaceae. 
Grows upon the river banks and in 
stagnant pools. I have found many sam- 
ples on the beach after heavy rain; they 
came evidently from the rivers. 
