“Color is the first revelation of the world,” said the Brazilian artist Hélio Oiticica (1937–1980). Known for his influence on Brazil’s avant-garde culture, Oiticica worked in the fields of visual art, theater, music, and literature. He often critiqued his native country, but also pushed for the expansion of traditional artistic methods. In an exhibition that spans both galleries, groundbreaking examples of Oiticica’s art are on display. At 24th Street, Oiticica’s installation Tropicalia (1966-67) uses sand, exotic birds, and flowers to address the clichés of Brazil’s association with paradise. Next door, Hunting Dogs Project (1961) is a beguiling maquette for a unrealized public garden. —E.C.