_Specimens examined._--Total number, 10 (4 males, 5 females, 1 unsexed), as follows: Mariana Islands, USNM--Guam, 2 (June 7, Sept. 1); AMNH--Guam, 3 (Aug. 15, 18, Nov. 30); Palau Islands, USNM--Peleliu, 3 (Sept. 7-12); Caroline Islands, USNM--Ulithi, 1 (Aug. 22); AMNH--Truk, 1 (Feb. 8). _Remarks._--According to Oustalet (1896:48), Lesson used two specimens of this species, which were collected in the Marianas by the expedition in the "Uranie," as types for his _Charadrius sanguineus_. The Mongolian Dotterel is a regular visitor to western Micronesia. It is recorded also from the Marshall Islands, which it probably reaches from the westward by way of the Carolines, since the species has not been recorded in the Hawaiian Islands. A bird taken by the writer at Guam on June 7, 1945, was in winter plumage and probably nonmigratory. The species was recorded also at Guam in September. At Peleliu in September, 1945, the Mongolian Dotterel was seen frequently on tidal flats by the NAMRU2 party. On September 8 there was a flock of approximately fifty birds, in company with _Charadrius leschenaultii_, at Akarakoro Point. In August at Ulithi, birds were on the beaches in company with _Crocethia alba_. At Angaur on September 21, 1945, the species was with other shore birds in small groups at fresh water ponds. I am tentatively referring all specimens examined to _C. m. stegmanni_ although at this writing (1948) I am inclined to the opinion that a critical reexamination of the referred specimens might reveal one or a few individuals of the subspecies _C. m. mongolus_ Pallas. =Charadrius leschenaultii= Lesson Large Sand Dotterel _Charadrius Leschenaultii_ Lesson, Dict. Sci. Nat., ed. Levrault, 42, 1826, p. 36. (Type locality, Pondichery, India.) _Charadrius griseus_ Lesson, Traité d'Ornith., 1831, p. 544 (Oulan). _Charadrius geoffroyi_ Hartlaub and Finsch, Proc. Zool. Soc. London, 1868, pp. 117, 118 (Pelew); _idem_, Proc. Zool. Soc. London, 1872, p. 89 (Pelew); Finsch, Journ. Mus. Godeffroy, 8, 1875, pp. 5, 31 (Palau). _Aegialitis geoffroyi_ Salvadori, Ornith. Papuasia, 3, 1882, p. 299 (Ualan, Pelew); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 64 (Pelew, Ualan). _Ochthodromus geoffroyi_ Sharpe, Cat. Birds British Mus., 24, 1896, p. 217 (Pelew, Ualan); Takatsukasa and Kuroda, Tori, 1, 1915, p. 62 (Pelew). _Pagoa leschenaultii_ Kuroda, in Momiyama, Birds Micronesia, 1922, p. 44 (Pelew, Kusaie, Yap). _Charadrius leschenaultii leschenaultii_ Hand-list Japanese Birds, rev., 1932, p. 193 (Yap, Kusaie, Palau); Hand-list Japanese Birds, 3d ed., 1942, p. 216 (Yap, Kusaie, Palau). _Charadrius leschenaultii_ Mayr, Birds Southwest Pacific, 1945, p. 38 (Micronesia); Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 51 (Peleliu).