Why it is called the Moor Fountain
The actual design of the fountain has frequently been called a bit lacking in originality. Even thought the fountain is quite perfect looking, the dolphins interaction with the Triton seems to just be an excuse show off the masculinity of the Triton. It is important to know that the face of the Titon is actually looking out into the distance, not focusing on the tremendous effort of wrestling the dolphin.
This fountain is still a very beautiful object, despite the aforementioned concepts in design. A very popular fountain among modern day Roman people. Due to the features of the face of the fountain, African like, the Romans refer to this fountain as the Moor Fountain.
The features themselves, which were copied from masks created by Michelangelo for the pillars atop of the Palazzo dei Concervatori, are often repeated in Bernini's work. It appears again in the Four Rivers Statues. The facical features were repeated by Bernini in the saddle of the elephant in PIazza della Minerva.