The species was common at Kalabakan. Garcia took a few at Quoin Hill, but I observed the species there only once.
Philentoma velata caesia (Lesson): Maroon-breasted Monarch Flycatcher.—Specimens, 7: Cocoa Research Station: ♀, 25.0 gm., August 4, 1962, MCT 2725; ♂, 27.2 gm., August 20, 1962, MCT 2783; ♂, September 5, 1962, MCT 2872. 12 mi. N Kalabakan: ♀, October 22, 1962, MCT 3126; sex? (♀ by plumage), October 29, 1962, MCT 3182; ♀, November 3, 1962, MCT 3205. 5.5 mi. SW Tenom: ♂, December 26, 1962, MCT 3536.
At Quoin Hill this was a bird of the primary forest. The species was common in the moss forest above Tenom.
Hypothymis azurea prophata Oberholser: Black-naped Blue Monarch Flycatcher.—Specimens, 18: Cocoa Research Station: ♀, 10.8 gm., August 10, 1962, MCT 2754; ♂, 15.2 gm., August 28, 1962, MCT 2834; ♂ testis 6 × 4 mm., 11.1 gm., September 6, 1962, MCT 2876; sex? September 14, 1962, MCT 2922; ♂, November 1, 1962, MCT 3200; ♂, November 7, 1962, MCT 3221; ♂, November 10, 1962, MCT 3242; ♂, November 20, 1962, MCT 3373; ♀, November 28, 1962, MCT 3374; ♂ testis 5 × 3 mm., December 1, 1962, MCT 3412; ♀, December 2, 1962, MCT 3427. 5.5 mi. SW Tenom: ♂, December 22, 1962, MCT 3504; ♂, December 23, 1962, MCT 3509. Cocoa Research Station: ♀, April 30, 1963, ADG 95; ♀, June 19, 1963, ADG 1551. Ulu Balung Cocoa Estate: ♂, July 11, 1963, ADG 194; Oil Palm Research Station: ♂, August 10, 1963, ADG 220; ♀, August 13, 1963, ADG 232.
This seemingly ubiquitous bird occurred in primary forest and cocoa. A specimen taken on September 14, 1962, was still in heavy molt.
Terpsiphone paradisi borneensis (Hartert): Paradise Flycatcher.—Specimens, 6: Cocoa Research Station: ♂ testis 9 × 5 mm., July 11, 1962, MCT 2616; ♂ testis 2 × 1 mm., 21.2 gm., August 3, 1962, MCT 2719; ♀, June 10, 1963, ADG 119. 12 mi. N Kalabakan: ♂, October 19, 1962, MCT 3090; ♀, November 10, 1962, MCT 3240. Oil Palm Research Station: ♀, August 24, 1963, ADG 258.
At Quoin Hill this species was common in primary forest. One of the males (MCT 2719) was rust-colored. It and similar rufous males may be immature (see Owen, 1963:235).
Pachycephala whiteheadi homeyeri (Blasius): Whitehead's Thick-head.—Specimens, 2: Siamil Island: ♀, September 19, 1962, MCT 2931; ♂, September 19, 1962, MCT 2932.
The thick-heads were by far the most common passerine bird in the relict forest on Siamil Island, being quite tame and easily approached. They generally spent most of their time sitting on branches of forest vines and bushes in the understory and were never observed in the upper story. McGregor (1910:604) describes the species as: "Common on Tawi Tawi, less so in Sulu. A deep woods bird; tame and easily shot. Feeds on insects, and usually keeps some distance above the ground."
The two specimens recorded above provide the first record of this species from Borneo, the previously known range being confined to the Philippine Islands. My material closely resembled the subspecies found on Tawi-Tawi and here is assigned to P. w. homeyeri.