A Naturalist in Indian Seas, or, Four Years with the Royal Indian Marine Survey Ship Investigator is a 1902 publication by Alfred William Alcock, a British naturalist and carcinologist. The book is mostly a narrative describing the Investigator's journey through areas of the Indian Ocean, such as the Laccadive Sea , the Bay of Bengal and the Andaman Sea. It also details the history of the Investigator, as well as the marine biology of the Indian Ocean. In its original edition, A Naturalist in Indian Seas was 328 pages long and published in 8 volumes in London.