_Poliolimnas cinereus micronesiae_ Hachisuka, Bull. British Ornith.
Club, 59, 1939, p. 151. (Type locality, Yap.)
_Ortygometra quadristrigata_ Hartlaub and Finsch, Proc. Zool. Soc.
London, 1868, pp. 8, 118 (Pelew); _idem_, Proc. Zool. Soc. London,
1872, pp. 90, 107 (Pelew, Uap).
_Ortygometra cinerea_ Finsch, Journ. Mus. Godeffroy, 8, 1875, pp.
5, 38 (Palau, Yap); _idem_, Proc. Zool. Soc. London, 1880, p. 577
(Ruk); Salvadori, Ornith. Papuasia, 3, 1882, p. 273 (Yap, Pelew);
Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6,
1890-1891 (1891), p. 61 (Pelew, Yap, Ruk); Finsch, Deut. Ver. zum
Schulze der Vogelwelt, 18, 1893, p. 459 (Palau).
_Ortygometra cinerea = quadristrigata_ Schmeltz and Krause,
Ethnogr. Abth. Mus. Godeffroy, 1881, p. 353 (Ruk).
_Poliolimnas cinereus_ Sharpe, Cat. Birds British Mus., 23, 1894,
p. 130 (Pelew, Yap, Ruk); Hartert, Novit. Zool., 5, 1898, p. 64
(Guam); _idem_, Novit. Zool., 7, 1900, p. 9 (Ruk); Scale, Occ.
Papers Bernice P. Bishop Mus., 1, 1901, p. 30 (Guam); Safford,
Osprey, 1902, p. 67 (Mariannes); _idem_, The Plant World, 7, 1904,
p. 265 (Guam); _idem_, Contr. U. S. Nat. Herb., 9, 1905, p. 79
(Guam); Cox, Island of Guam, 1917, p. 21 (Guam); Kuroda, in
Momiyama, Birds Micronesia, 1922, p. 42 (Guam, Pelew, Yap, Ruk).
_Porzana cinerea_ Stresemann, Novit. Zool., 21, 1914, p. 54 (Guam,
Truk).
_Porzana cinerea ocularis_ Hartert, Novit. Zool., 31, 1924, p. 264
(Ruk, Guam).
_Poliolimnas cinereus collingwoodi_ Mathews, Syst. Avium
Australasianarum, 1, 1927, p. 95 (Pelew, Marianne, Carolines);
Hand-list Japanese Birds, rev., 1932, p. 197 (Guam, Koror, Yap,
Truk); Hachisuka, Birds Philippine Islands, 1, 1932, p. 236
(Marianne, Pelew, Caroline); Peters, Check-list Birds World, 2,
1934, p. 198 (Marianne, Caroline, Pelew); Bryan, Guam Rev., vol.
13, no. 2, 1936, p. 15 (Guam); Mayr, Birds Southwest Pacific,
1945, p. 288 (Guam, Palau, Yap, Truk, Bikini); Delacour and Mayr,
Birds Philippines, 1946, p. 64 (Micronesia); Baker, Smithson.
Misc. Coll., vol. 107, no. 15, 1948, p. 48 (Ulithi?, Truk).
_Porzana cinerea collingwoodi_ Rensch, Mitt. Zool., 1931, p. 468
(Marianne, Karolinen, Palau).
_Poliolimnas cinereus micronesiae_ Yamashina, Tori, 10, 1940, p.
679 (Bikini); Hand-list Japanese Birds, 3d ed., 1942, p. 221
(Guam, Babelthuap, Koror, Yap, Truk, Bikini).
_Geographic range._--Micronesia: Mariana Islands--Guam; Palau
Islands--Koror, Babelthuap; Caroline Islands--Yap, Ulithi?, Truk;
Marshall Islands--Bikini.
_Characters._--Adult: A slightly built, long-legged rail with
forehead and anterior crown light gray with darker, slate-colored
feather shafts; color more olive-brown on occiput and nape;
eyestripe dark slate extending to occiput; superciliary from bill
to eye, and stripe below eye, white; chin and throat ashy-white;
sides of head, neck and breast ashy-gray, lighter on breast and
whitish on abdomen; sides of abdomen ashy-brown becoming more
buffy on tibia and under tail-coverts; mantle olive-colored
becoming lighter and more brownish on back, rump, and scapulars;
wing-coverts similar in color but feathers with broad dark brown
shaft-marks; wings brown, first primary with whitish outer web;
under wing gray with some lighter streaks; tail dark brown,
lighter on edges; bill horn colored, tan below; feet brown; iris
vermillion.
Immature: Resembles adult, but head more rufous, upper parts
marked with buffy rufous; eye stripe light rufous-brown;
underparts tinged with rufous.
_P. c. micronesiae_ differs from _P. c. collingwoodi_ Mathews of
the Philippines by having more pale gray and less olivaceous-brown
on the nape and shoulder; darker on the under tail-coverts; and
having a shorter culmen. _P. c. brevipes_ (Ingram) of the Volcano
Islands differs from _P. c. micronesiae_ by being paler on upper
parts, particularly back and wing-coverts and more washed with buff
below; by having a shorter, thicker culmen; and by having a shorter
tarsus.
_Measurements._--Measurements are shown in table 17.