Encyclopedias, Almanacs, Transcripts, and Maps
- Passenger Pigeon
- Passeriformes (continued)
- Passeriformes (Perching Birds)
- Passive Solar Design
- Passmore, John Arthur (1914 – ) Australian Philosopher and Writer
- Pasternak, Boris
- Patañjali the Grammarian
- Patellogastropoda (True Limpets)
- Patriarchy and Matriarchy
- Patrick
- Paucituberculata (Shrew Opossums)
- Pauck, Wilhelm
- Paul the Apostle
- Pauropoda (Pauropods)
- Peat Soils
- Peatlands
- Peccaries (Tayassuidae)
- Pecham, John
- Pedology
- Pelagic Zone