_Remarks._--The Nightingale Reed-warbler at Guam is restricted to cane thickets and adjacent areas in and near fresh and brackish water marshes. In 1945, the NAMRU2 party found the bird fairly numerous in some of these habitats. Seale (1901:53) writes, "This bird is now quite scarce on the island of Guam. It lives exclusively among the reedy swamps, and those swamps are now being drained to make room for the Chinaman's rice paddies." Mayr (1945a:295) also notes the rarity of the species. As a result of the late war, the cultivation of rice was reduced and the reed-warbler probably has been able to increase in some of the now fallow areas. The most extensive range of this bird at Guam is found in the Agaña Swamp, where there is a large area consisting of thick cane. Here, and in the other large cane patches, the chief hazard to the bird population appears to be fire. In dry periods, the entire habitat might be easily destroyed by fire. The birds are extremely shy; their melodious songs may be heard in the reeds, but their active movements in the thick cane are difficult to observe. While hunting for these birds along the edges of Agaña Swamp on June 2, the writer observed, or located the calls of, at least six or seven individuals but could only get within shooting range of three birds. Within the cane thickets, these birds feed and move about near the ground or the surface of the water. Rarely do they perch in a conspicuous manner in the upper parts of the cover. Their color patterns blend perfectly with the coloration of the dry cane stalks. Perhaps failure to find many of the birds because of their secretive habits has caused many observers to assume that the bird is near extinction. Nevertheless, it is my contention that the bird, being restricted to these limited areas, has never been very abundant at Guam. The absence of natural enemies, especially snakes, may be one of the principal reasons why they have been able to survive. Reed-warblers were not found by the NAMRU2 party at Rota in 1945, nor have they been reported from Tinian. Yamashina in 1942 described the populations at Saipan and Almagan as distinct. I have not seen this description, but on the basis of examinations of specimens from Saipan, I can see no recognizable differences between these and birds from Guam. =Acrocophalus luscinia syrinx= (Kittlitz) Nightingale Reed-warbler _Sylvia syrinx_ Kittlitz, Mém. Acad. Imp. Sci. St. Petersbourg, 2, 1835, p. 6, pl. 8. (Type locality, Lugunor and Ulcei = Woleai.) _Sylvia syrinx_ Kittlitz (part), Obser. Zool., in Lutké, Voy. "Le Séniavine," 3, 1836, p. 297 (Lougounor); _idem_, Denkw. Reise russ. Amer. Micron. und Kamchat., 2, 1858, p. 92 (Ualan, Lugunor, Ulea). _Eparnetes_ Reichenbach, Syst. Avium, 1850, pl. 57 (no locality = Carolines); Bonaparte, Comptes Rendus Acad. Sci. Paris, 41, 1855, p. 1111 (Carolines).