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Studies on the stomata of Potamogeton.
by Shinobu R. (1952)
Shinobu Riyuji, Osaka Liberal Arts University , Hirano Branch
in Bot. Mag., Tokyo. 65: 765-766
The author reports finding many stomata on the upper surfaces of floating leaves of Potamogeton distinctus, P. malainoides, P. natans, P. frayeri, P. gramineus, and P. cristatus.
On most of these a’few were also found on the lower surfaces. This is interpreted as a survival from a previous terrestrial state and it is suggested that Potamogeton has affinity with either the Synanthae or Pantanales, rather than with the Helobie.