From 1944 to 1950, Miró created a dozen small-scale major works featuring a series of characters, highly stylised heads and birds that he modelled in clay and reproduced in bronze and terracotta. The plaster versions of many of these works have been part of the MACBA Collection since they were acquired as part of the collection of gallery owner Salvador Riera in 1997. These works include the female figures Femme, Dona, Sense títol (Cap de dona) and Sense títol (Dona); an unspecified character, Sense títol (Personatge); and the birds Ocell (solar) and Sense títol (Ocell lunar). Miró modelled the volumes in the manner of a ceramicist: these sculptures are solid, rounded bodies with large protuberances and indentations, clefts and symbols. One of the main figures is an opulent woman, like a new primitive Venus or a mother-goddess, a figure that lies at the heart of Mirò's symbolic imaginary. Birds also have a strong presence, and would later inspire some of Miró's monumental sculptures. Ocell (solar) and Sense títol (Ocell lunar) are the best-known of these. Miró produced drawings, plaster casts and small bronzes of both as studies for subsequent large-scale works. While the vertical, dynamic Sense títol (Ocell lunar) seems more closely connected to the earthly sphere, Ocell (solar) is horizontal and static, and clearly evokes a bird. Both of these works suggest a cosmic duality that is a recurring element in Miró's work: the play of opposing and complementary forces between sun and moon, day and night, female and male principles.