Lilies are tall perennials ranging in height from 2–6 ft (60–180 cm). They form naked or tunicless scaly underground bulbs which are their organs of perennation. In some North American species the base of the bulb develops into rhizomes, on which numerous small bulbs are found.[from wikipedia]

Daylilies are perennial plants, whose name alludes to its flowers, which typically last about a day. The flowers of most species open in early morning and wither during the following night, possibly replaced by another one on the same scape the next day. Some species are night-blooming. Daylilies are not commonly used as cut flowers for formal flower arranging, yet they make good cut flowers otherwise, as new flowers continue to open on cut stems over several days.[from wikipedia]

You'll be thrilled with the awesome flower power displayed by this heavily budded rebloomer! Inwood is a prolific "fancy face" daylily that bears plenty of uniform, soft peachy cream flowers with a bold plum-purple eye. The 6½" blooms attract butterflies (and loads of attention) to borders and beds. Hemerocallis[from brecks]

Despite their common name, daylilies are not true lilies (plants from the genus Lilium, family Liliaceae). Although the flowers of Hemerocallis and Lilium species have a similar shape, their growth habits, stems and leaf shapes are distinctive.[from wikipedia]