Notes on the Flora of Caroline Atoll by C. R. Long Caroline Atoll situated between 150 14' and 150 13 west longitude and 9 55' and 10 55' south latitude is composed of three large islands. Two of these, Nake Island and Long Island are separated by a mud flat at low tide. Together these two islands form a land mass approximately 2.2 miles long at the north end of the atoll. South Island is about 1 mile wide and .35 miles long at the widest point. In between these islands which form the north and south extremities of the atoll are numerous small islets ranging from a few acres to less than a half acre in extent. The largest of these Arundel, Brothers and Pig Islands lie on the windward side of the atoll. Many of the smallest islets are found on the leeward side. The atoll is approximately 5.35 miles long with the land mass lying at an angle to the northeast as far as the southern extremities of Long Island and curving toward west of north along the length of Long Island and Nake Island. Vascular plants were collected on June 17 and 18, 1965 under the auspices of the Pacific Ocean Biological Survey Program, Division of Birds, Smithsonian Institution. Herbarium sheets are deposited in the herbarium of the University of Hawaii with duplicates, where available, in the herbaria of the United States National Museum and the Bishop Museum. Vascular plants were recorded (collection and whereabouts uncertain) by Bennett (Bennett, 1840) and later a number of specimens were collected by Dixon (see Trealease, 1884). The latter collection has been examined with the cooperation of Dr. Hugh H. Iltis, Curator of the herbarium of the University of Wisconsin. Collection numbers are those of my serial sequence. PSILOPSIDA