Copeland (1947) assigned Pilularia L., Regnellidium Lindm. and Marsilea L. to the Marsileaceae and separated the genera on the basis of frond-form and the number of leaflets. In Pilularia L. the frond is filiform or grasslike, Regnellidium Lindm. and Marsilea L. are bifoliate and tetrafoliate respectively.
Chromosome number of Pilularia caroliniana A. Br.
- Nardinder Chopra
- December - 1961