Denis Marie Emmanuel Lamy, better known as Denis Lamy, officially retired in December 2013 from the muséum national d’Histoire naturelle – hereafter referred to as MNHN (www.mnhn.fr) – where, fortunately, he continues to work as an honorary associate, and corresponding member of the Alexandre-Koyré Centre (EHESS, MNHN, CNRS) (koyre.ehess.fr).
Alongside the many valuable services rendered to both Botany in general and the Museum in particular, Denis has greatly contributed to bryology, maintaining a special relationship with many bryologists around the world. For this reason, on the occasion of his 70th birthday, a group of colleagues from different countries and continents wish to dedicate this fascicle of the Journal to him, as an expression of our gratitude for his contribution to Bryology, and also for his continuous and generous help to bryologists from different parts of the World over the last four decades. To complement the words of appreciation written in his honour on his retirement (LeGall et al., 2015. In honor of Denis Lamy. Cryptogamie, Bryologie, 36: 209-210), the following account is intended to present a synthesis – necessarily incomplete – of his achievements in the management of scientific documents, as well as in scientific research, teaching and the promotion of botanical science.