Cyfyngwch eich canlyniadau yn ôl:
- Pob un
- Lhuyd, Edward, 1660-1709, 7 canlyniadau
- Bingley, William, 1774-1823, 2 canlyniadau
- Chater, A. O., 2 canlyniadau
- Ray, John, 1627-1705, 2 canlyniadau
- Roberts, Evan, 1906-1991, 1 canlyniadau
- Roberts, Brynley F, 1 canlyniadau
- Chater, A. O. -- Correspondence., 1 canlyniadau
- Benoit, Peter Michael, 1931- -- Correspondence, 1 canlyniadau
- Bowen, E. G. (Emrys George), 1900- -- Correspondence, 1 canlyniadau
- Ratcliffe, Derek, 1929- -- Correspondence., 1 canlyniadau
- Pob un
- Natural history -- Wales -- Cardiganshire, 2 canlyniadau
- Natural history -- Wales -- Snowdonia, 1 canlyniadau
- Landscape -- Wales -- Snowdonia, 1 canlyniadau
- Milvus -- Europe, 1 canlyniadau
- Lilies -- Wales -- Snowdonia, 1 canlyniadau
- Mountain plants -- Wales -- Snowdonia, 1 canlyniadau
- Natural areas -- Spain., 1 canlyniadau
- Plant collecting -- Wales -- Cader Idris, 1 canlyniadau
- European polecat, 1 canlyniadau
- Tourism -- Wales -- Snowdonia, 1 canlyniadau