Key, Leptogium, Mallotium, Himalayas, Asia. The features of the Section Mallotium are described, and attention is drawn to the dimensions of the parathecium as a potentially important taxonomic character. A key is provided for the nine Himalayan taxa of the Section. The occurrence of clusters of short hairs on the upper surface of the thallus is noted in the case of L. hildenbrandii and L. saturninum. Reference is made to the uncertain taxonomic status of L. inflexum var. isidiosulum.