Terrestrial Orchids, is part of a research program to study and photograph orchid species from the Eastern Himalayas, covering the regions of Eastern Nepal, Sikkim, Darjeeling district, Arunachal Pradesh, Assam and Nagaland. Two monumental publications-The Flora of British India (1890) by Sir J.D. Hooker and The Orchids of the Sikkim Himalaya (1898) by Sir George King and Robert Pantling were relied on. Each species was located in its natural habitat and documented while in bloom, ample time was devoted for this purpose, thereby updating the flowering time precisely, altitudinal range widely, habitat proximately and natural characteristics to detailed perfection. The study also focused on preparing a status report on the population of each species to initiate various conservation programs. I, till date, am successful in compiling documentary evidence of 780 species of orchids in the region of Eastern Himalayas, trekking more than 45000 km on foot. This publication, the first of its kind, is a collection of 108 rare to very rare ground orchids in the region. Majority of them are the first ever photographic evidence. During the course of study, not a single specimen was collected nor damaged. Religiously utmost care was taken so as not to disturb the sanctimonious habitat of the studied specimens. The nomenclature of each species is in accordance with the current World Checklist of selected plant families, Kew Royal Botanic Gardens. (jacket)