Ina is a peculiar small depression , in Lacus Felicitatis. It is D-shaped, 2.9×1.9 km wide and 64 m deep Ina is remarkable for several dozens of low hills with flat or rounded tops and very sharp rounded boundaries, looking like drops of mercury. Their surface looks like usual surface , and the space between them is strongly different. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On the Moon they are named after deceased scientists, polar explorers, astronauts or cosmonauts.
