Acanthophora, a Possible Invader of the Marine Flora of HawaiF

by Mr. Charles Cutress. In April, 1953, a much larger piece of the alga was brought in by Mr. Spencer Tinker, who had found it washed ashore near the Waikiki Beach Laboratory of the Uni-versity of Hawaii. Both collections were readily determined as representing a species of Acan-thophora Lamouroux (1813: 132), a rhodo-phytan genus. This genus is distinct and clearly recognizable among the floral elements occur-ring in this part of the world. A search of the literature and the herbaria available revealed no Pacific records of this genus from the Ha-waiian Islands or, with one exception, east- of the Western Caroline and Marianas islands north of the equator. Other collections during succeeding years, and field observations as well, revealed a huge in-crease in the abundance of the species in Ha-waii during the next few years. In May, 1953, Dr. D. W. Strasburg found this alga "in abun-dance " at Keehi Lagoon, between Pearl Harbor and the Port of Honolulu on the leeward side of Oahu. Later the same month, a dense growth of the alga was found by the author (numbered 10774) and Dr. E. Y. Dawson at Hauula, north of Honolulu, on the windward side of the is-land of Oahu. Parts of this collection are the earliest collections from Hawaii represented in both the Bishop Museum and the University of California herbaria. From that time on, Acan-thophora has been so common on the leewar