Nemesia seed. Coloured scanning electron micrograph (SEM) of a seed from a nemesia plant. Nemesia is a genus of annuals, perennials and sub-shrubs which are native to sandy coasts or disturbed ground in South Africa. Numerous hybrids have been selected, and the annual cultivars are popular with gardeners as bedding plants.A seed is an embryonic plant enclosed in a protective outer covering. The embryo is developed from the zygote and the seed coat from the integuments of the ovule. Seeds are very diverse in size. Plants that produce smaller seeds can generate many more seeds per flower, while plants with larger seeds invest more resources into those seeds and normally produce fewer seeds. Magnification: x35 when printed at 10 centimetres wide.