Morphology and Cytology of Vallisneria spiralis L.

The order Helobiae, to which the species under discussion belongs, has been an especially inviting field for morphological study. Many of the species have been investigated. Specialized features have been found which appear particularly advantageous for plants that live under aquatic or partially aquatic conditions. On the other hand, some unspecialized features have also been observed, and of which it may be a question whether they really represent a fundamental simplicity in the plant structure or whether they are generalized features allowed or necessitated by the comparative evenness of aquatic conditions.