Chloroplasts ofMacrozamia mooreiwere observed in submature and mature leaves. Prolamellar bodies and crystalline bodies are an obligate feature in the course of chloroplast development and appear related to thylakoid membrane formation. Mature chloroplasts show randomly oriented grana constituted by a very high number of thylakoids (up to 180 per granum). The probable existence of a cycad-type chloroplast is proposed.