144 NILS GYLDENSTOLPE, ZOOLOGICAL RESULTS OF THE SWEDISH ZOOLOGICAL EXPEDITIONS TO SIAM. 
It was generally mixed up among the flocks of O. mongolus Pau. and.Aegialites 
alexandrina LINN. 
The specimens obtained were all shot on a sandy beach, and all are in their winter 
plumage. 
309. Ochthodromus mongolus. Patt. — The Lesser Sand Plover. 
Aegialites mongolica: Gyldenstolpe I p. 69. 
Aegialites mongolicus: Grant p. 118. 
Q Koh Lak ?°/11 1914. L = 180 mm; W = 136 mm.; = 53 mm.; C = 20 mm.; Tarsus = 30 
mm. — Irides: brown. Bill: black. Legs: greyish yellow. 
a 
The Lesser Sand Plover is a winter visitor to the coasts of Siam, but seems to be 
rather rare and only a few specimens, probably belonging to this species, were observed. 
The only one I obtained was shot on a sandy beach south of Koh Lak on the 29th of 
November 1914. 
The allied form O. pyrrhothorax GOULD. is very similar to O. mongolus Patt, 
in its winter plumage, being only separated by its slightly longer tarsus. It probably 
occurs in Siam too. 
310. Aegialites dubia. Scop. —- The Little Ringed Plover. 
Aegialites dubia: Williamson I p. 48; Gyldenstolpe Il; Gyldenstolpe III p. 235; Grant p. 118; Gairdner p. 152. 
¢ Koon Tan °8/, 1914. L = 152 mm.; W = 104 mm; T = 55 mm; C= 13 mm. — ¢ Koon Tan 
30/7 1914. L—= 145 mm.; W = 102 mm. T = 58 mm.; C = 12 mm. — Irides: brown. Bill: black (base 
of lower mandible yellow). Legs: light brown. 
I never found this Plover mixed up among the other kind of Sand Plovers which 
occurred in large numbers along the coasts of the Gulf of Siam. 
In the Northern parts of the country it was, however, not uncommon during the 
winter months. It was found on the sandbars in the larger rivers and creeks. My 
specimens were both obtained at the Meh Tha river where it passes through the Koon 
Tan mountains. 
311. Aegialites peroni. Br. —- The Malay Sand Plover. 
JS Koh Lak 1/12 1914. L = 143 mm; W = 90 mm; T = 43 mm.; C = 16 mm. — 2 Koh Lak 
18/9 1914, L = 145 mm; W = 99 mm.; T = 43 mm; C = 16 mm. — Y Koh Lak !%/i2 1914. L = 150 
mm.; W = 96 mm.; T = 45 mm.; C = 15 mm. — Irides: brownish black. Bill: black. Legs: greyish white. 
Three specimens of this rare bird which inhabits the Indo Malayan Archipelago 
where obtained south of Koh Lak in December 1914. 
They occurred either single or in pairs and were never mixed up among the flocks 
of the other kind of wading-birds such as A. alexandrina Linn. or Ochthodromus geoffroyi 
Waat. which were rather common on the sandy beaches south of Koh Lak. 
As far as I know this is the first record of this bird from Siamese Territory and it has 
never been recorded from the Malay Peninsula nor from Burma or Tenasserim. 
