Amphitrite of the Blue Waves was the daughter of Nereus and grand-daughter of Oceanus. She was seen dancing on the shores of Naxos by Poseidon who instantly fell in love with her. Dolphins ultimately persuaded Amphitrite to marry the Sea God, and so she is usually portrayed with them as her escort.
Cybele, Magna Mater, was viewed as the mother of all Life. She was held in particular reverence by women who prayed to her for successful childbirths. Cybele was also identified with Demeter, Mother of the corn, another female deity associated with fertility and fruitfulness, hence the sheafs held by the goddess in this example.