In Family Solanaceae they are known as Eggplants.
Some are seen under names such as S. melongena var. depressum, S. melongena var. esculentum,
S. esculentum and S. melanocarpum although the Plant List, Kew and some eFlora sites
say these are all synonyms of Solanum melongena.
They are perennial herbs, sometimes shrub-like, usually grown as annuals.
From 0.5 to 1.5 m in height the branching stems are green or purple.
Stems are covered in stellate hairs, sometimes with glands, and often have prickles.
The alternate leaves are 10 to 20 cm long and 5 to 10 cm wide.
The long petioles have hairs and may have prickles.
The ovate blades can be simple but typically have coarse, shallow to deep lobes.
The tips are pointed and the base is unequal.
The green leaves appear greyish due to the soft, stellate hairs on both surfaces.
Prickles are rarely seen on the leaves.
Inflorescences are mostly a solitary flower but can be a cluster of up to 5.
Flowers are star-shaped, 3 to 5 cm across, and purple or bluish (occasionally almost white).
Flowers can be various combinations of bisexual and male.
The bases of 5 sepals are fused into a cup or tube with unequal, narrow lobes.
The calyx often has dense hairs on both surfaces and spines externally.
The fused bases of the 5 petals hold deep or shallow, pointed lobes.
There are hairs on the outer surface and a few on the inner midrib.
The 5 stamens, on short filaments, insert into the corolla tube.
The yellow anthers open via apical pores.
The superior ovary has 2 locules with axile placentation.
The single style has stellate hairs at the base.
The size of the ovary and length of the style varies between plants and varieties.
The fruit are glossy, fleshy berries with a calyx that enlarges as the fruit grows.
They have many small, pale or black seeds.
The hundreds of eggplant cultivars vary mainly in the size, shape and colour of the fruit.
They can be up to 45 cm long and 35 cm wide.
Shape varies from round to oval, pear-shaped, cylindrical or oblong.
Colours include black, purple, yellow, green or white and some are striped.
Commonly cultivated in Australia the dark purple or black ovoid ones up to 25 cm.