most european and american geologists dated lemuria's disappearance to a period before the emergence of modern humans. thus, according to them, lemuria could not have hosted an ancient civilization. however, in 1885, the indian civil service officer charles d. maclean published "the manual of the administration of the madras presidency", in which he theorized lemuria as the proto-dravidian urheimat. in a footnote in this work, he mentioned ernst haeckel's asia hypothesis, which theorized that the humans originated in a land now submerged in the indian ocean. maclean added that this submerged land was the homeland of the proto-dravidians. he also suggested that the progenitors of the other races must have migrated from lemuria to other places via south india. this theory was also cursorily discussed by other colonial officials like edgar thurston and herbert hope risley, including in the census reports of 1891 and 1901. later, maclean's manual came to be cited as an authoritative work by the tamil writers, who often wrongly referred to him as a "scientist" and a "doctor".