Talk about the phylum of spermatophytes.

Seed plants, phanerogams. Seeds replace the spores in the developmental cycle. Male and female gametophytes are very small and develop inside specialized organs in the sporophyte which gives them protection against desiccation... After fertilization, the ovule becomes a seed. All spermatophytes posses megaphylls, but are transformed into needles or scales in some groups. The spermatophytes are divided into two sub-phylums: angiosperms and gymnosperms