Plants of the Indian desert belonging to 29 families, 85 genera and 105 species of angiosperms were screened for the possible occurrence of the C-pathway of photosynthetic CO-fixation. The criteria used for screening were leaf anatomy and/or δC values. The results indicated the occurrence of the C-pathway in members of 3 new families (Acanthaceae, Cleomaceae, Scrophulariaceae), 10 new genera (Aerva, Anticharis, Blepharis, Elyonurus, Glossocardia , Gynandropsis, Melanocenchris, Sehima, Sesuvium, Zalaeya) and 34 new species of the angiosperms. All the grasses investigated were found to possess the C-pathway. Cuscuta hyalina, a phloem-parasite, growing on C hosts (Tribulus, Zalaeya) also revealed δC value very close to that found in the host plants.