_Characters._--Adult: A large, slender rail with black crown streaked with brown; superciliary stripe ashy-gray, lighter toward bill; eye stripe brown becoming more rufous behind eye and on nape; chin ashy-gray; throat near "mouse gray" tinged with olive especially toward breast; breast, belly and sides barred with black and white, with a broad "tawny" band on breast; posterior part of belly and vent buffy with some barring; under tail-coverts barred with black, white, and buff; mantle black with feathers subterminally barred with white; back, scapulars, inner wing-coverts, and rump black with white spotting and feathers edged with olive brown; outer wing-coverts, secondaries, and primaries barred with black and rufous with some buffy-white on outer webs; under wing barred black and white with some brownish markings; tail with both bars and blotches of black, white, and buffy-rufous; maxilla horn-colored; mandible yellowish; feet light brown. _R. p. pelewensis_ resembles _R. p. philippensis_ Linnaeus of the Philippines, but is darker with nape more rufous-brown; upper parts marked with narrower and darker edgings to feathers and with pronounced whitish spotting. Resembles _R. p. chandleri_ (Mathews) of Celebes, but with wing shorter; more pronounced band on breast; bird darker above and below; rump and upper tail-coverts less spotted. _Measurements._--Specimens in the collection of the United States National Museum measure as follows: four adult males--wing, 130-134 (132); tail, 59-63 (61); full culmen, 30-37 (34); tarsus, 38-45 (43); four adult females--wing, 125-130 (127); tail, 54-61 (58); full culmen, 29-35 (32); tarsus, 38-42 (40). Mayr (1933c:4) lists the following measurements: twelve adult males--127-143 (134.6); tail, 54-65 (60); exposed bill, 25-28 (27.7); tarsus, 41-46 (43.5); three adult females--wing, 129, 136, 136; tail, 56, 57, 58; exposed bill, 23, 24, 25; tarsus, 40, 41, 42. _Specimens examined._--Total number, 27 (18 males, 9 females), as follows: Palau Islands, USNM--Garakayo, 4 (Sept. 18, 19, 20)--Peleliu, 4 (Aug. 27, 28, Sept. 16)--Arakabesan, 1 (Nov. 26); AMNH--exact locality not given, 18 (Oct., Nov., Dec.). _Nesting._--The condition of the gonads in specimens obtained indicates that the breeding season is principally in the fall and winter. Of adult rails taken by Coultas in October, November and December, 1931, 6 of 12 males and 3 or 4 females had enlarged gonads. In September, 1945, the NAMRU2 party obtained two adult males with swollen testes. Marshall (1949:219) recorded breeding in September and November.