Description of a new bird from Simalur

During my work on Simalur birds (cf. Temminckia, vol. 1, 1936) I compared the specimens of Charadrius peronii from this island with the specimens from Borneo and Semao in our Museum. Though the Simalur birds were darker I did not pay much attention to this fact, as our material from these localities were mounted birds of about a century old and I feared these specimens were so badly faded, that no satisfactory comparison could be made. During his recent stay in the Leiden Museum mr F. N. Chasen noted the same fact and promised to send a good series of fresh skins. I was now able to compare the Simalur specimens with 4 ♂♂, 5 ♀♀ from North Borneo; 2 ♂♂, 1 ♀ from NE Malay Peninsula; 1 ♂ from the Rhio Archipelago; 1 ♀ from Pulau Tioman, S China Sea. It appeared that mr Chasen's suggestion was quite correct and that the Simalur form needs separation. Charadrius peronii chaseni nov. subspec. Diagnosis : Compared with the nominal race chaseni is darker on the upper parts, less rufous on the head, especially in the ♀♀. Also the rufous colour behind the white neckcollar and on the sides of the breast is much more pronounced in p. peronii. The bill in chaseni is slightly heavier. Type: A ♀ collected at Lasikin (Simalur) on 6-4-1913 by Jacobson and van Heurn (no. 607).