What exactly do you mean by "black lily"? Do you know the botanical name? Unfortunately, dozens of plants are referred to as "lilies" that are not so 'black lily' is not very meaningful, especially if we are discussing proper propagation. Just for clarification, there are no real "black" lilies, although some have very dark red flowers :-)

If this is a true lily, like an Asiatic or oriental hybrid, they are rather easily grown from seed although this is not considered the fastest way to generate new plants.

Here is a link that might be useful: growing lilies from seed

I surmised it's the seeds that are black. Are they the bulbils that form between the stem and leaf axils on, say, a true tiger lily (lilium tigrinum lancifolium)? If so, they're falling naturally from the mother plant now so this is the right time to put them lightly under the soil where you want them to sprout.

I'm sorry I don't know the name it's what DF called them.
Thanks

Can you check with them as to the correct botanical name? Different seeds require different methods for germination and unless we can pin it down as to specific kind of lily (true lily versus common name lily), it is all just speculation.

I too have seeds from lilies i bought at a nursery. They fell from seed pods after the petals fell off. I'm confused because from what I've read they sound nothing like lily seeds. Anyone know what they are?

The attached link illustrates the seed pods and seeds of a true lily. It also explains how to grow them from seed. Anything that looks significantly different from this is probably not a true lily seed.

Bulbils - those little black berry-like nubs that are found on some lilies tucked in at the leaf axils - are not seeds but sort of baby bulbs. You can also plant them like you would plant a row of sweet peas and in a couple of years have full size bulbs. But not all lilies will produce bulbils - tiger lilies and many of the Asiatic hybrids are the most common sources.

Here is a link that might be useful: growing lilies from seed

sounds like blackberry iris have they come up yet