Milfoil, Wateramily: N.O. Haloragaceae
To the same natural order as the Mare's Tail (Haloragaceae) belongs the Water Milfoil, which has the following varieties: SPIKED WATER MILFOIL (Myriophyllum spicatum), an aquatic plant forming a tangled mass of slender, much branched stems; Ieaves, four in a whorl, finely divided into numerous hair-like segments, the whole plant being submerged, except the spikes of inconspicuous greenish flowers, which rise a few inches above the surface.
WHORLED WATER MILFOIL (M. verticillatum) differs from the preceding in having the flowers in whorls at the base of the leaves: alternate-flowered Water Milfoil (M. alterniflorum) has the barren flowers alternately arranged in a short leafless spike, with the fertile flowers about three together, in the axils of the leaves, at its base. Both species are rare.
See MARE'S TAIL.