Infructescence: Sparganium americanum; Photo by R. Gibbons, USDA APHIS PPQ, Kirkbride et al. (2006)
Fruits: Sparganium americanum; Photo by R. Gibbons, USDA APHIS PPQ, Kirkbride et al. (2006)
Seed: Sparganium americanum; Photo by R. Gibbons, USDA APHIS PPQ, Kirkbride et al. (2006)
Embryo: Sparganium americanum; Illustration by K. Parker, Kirkbride et al. (2006)
Fruits: Sparganium erectum; Photo by Julia Scher, USDA APHIS PPQ, bugwood.org
Embryo: Typha angustifolia; Illustration by K. Parker, Kirkbride et al. (2006)