Ferns reproduce using spores, not seeds. Plants that reproduce using spores, like ferns, are called spore-bearing plants or cryptogams. Here are some examples:

* Mosses: These small, non-vascular plants are commonly found in damp, shady environments. They also reproduce using spores.

* Liverworts: Similar to mosses, liverworts are non-vascular plants that reproduce using spores. They have a flat, lobed appearance.

* Hornworts: These small, non-vascular plants are named for their horn-shaped sporophytes. They also reproduce using spores.

* Clubmosses: These vascular plants are not true mosses but resemble them in appearance. They have a creeping stem with small, scale-like leaves and reproduce using spores.

* Horsetails: These vascular plants have a distinctive jointed stem and are commonly found in wet environments. They also reproduce using spores.

* Lycophytes: This broad category includes clubmosses, spikemosses, and quillworts, all of which reproduce using spores.

While these plants all reproduce using spores, they are not necessarily related to ferns. They represent different groups of plants that evolved independently to use spores as their primary mode of reproduction.