 In 1863 he was elected president of the "Société botanique de France", and from 1873 to 1889, he was a member of the "Académie des sciences".In 1882 Jules Ferry, as Minister of Public Instruction, decided to create a mission to explore the Regency of Tunisia.The expedition was headed by Cosson and included the botanist Napoléon Doumet-Adanson and other naturalists.