The specimens were netted in scrub-grassland at Tenom. The size of the testes of the Tenom specimens indicated that the birds were breeding.
Pycnonotus brunneus brunneus Blyth: Red-eyed Brown Bulbul.—Specimens, 17: Cocoa Research Station: ♂ imm., 32.6 gm., July 22, 1962, MCT 2638; ♂ testis minute, 37.3 gm., August 2, 1962, MCT 2709; ♂ testis minute, 36.0 gm., August 3, 1962, MCT 2720; ♀ ovary granular, September 4, 1962, MCT 2867; ♂ testis 6 × 4 mm., September 4, 1962, MCT 2868; ♀ egg in oviduct, largest ovum 9 mm., 1 collapsed follicle, 30.0 gm., September 10, 1962, MCT 2894; ♂ testis small, September 25, 1962, MCT 2953; ♀, September 25, 1962, MCT 2954; ♂ testis small, November 27, 1962, MCT 3346; ♂ testis 4 × 2 mm., November 29, 1962, MCT 3380; ♂ testis small, November 29, 1962 MCT 3393; ♂ testis small, December 1, 1962, MCT 3402; ♂ testis small, December 1, 1962, MCT 3403; ♂ testis small, December 1, 1962, MCT 3404; ♀ ovary minute, December 1, 1962, MCT 3416; ♂ testis small, November 30, 1962, MCT 3438. Oil Palm Research Station: ♀, August 27, 1963, ADG 260.
This most common of the "brown" bulbuls at the Cocoa Research Station frequented shade trees (Trema orientalis). One bird fed on small red peppers, Capsicum sp. Some of the September-taken specimens were in breeding condition.
Pycnonotus simplex perplexus Chasen and Kloss: White-eyed Brown Bulbul.—Specimens, 3: 5.5 mi. SW Tenom: ♀ ovary granular, December 19, 1962, MCT 3469; ♂ testis 4 × 3 mm., December 20, 1962, MCT 3478; ♀ ovary granular, December 22, 1962, MCT 3499.
This bird was taken only in the moss forest at 4,000 feet elevation near Tenom. Smythies (1960:382) considered the species to be characteristic of the lowlands. Specimens were taken by Harrison in the Kelabit Uplands (Smythies, 1957:704) at 4,200 feet.
Pycnonotus erythrophthalmos salvadori (Sharpe): Lesser Olive-brown Bulbul.—Specimens, 15: Cocoa Research Station: ♂ testis 6 × 4 mm., 20.2 gm., August 12, 1962, MCT 2778; ♂ testis 6 × 5 mm., 19.8 gm., August 28, 1962, MCT 2830; ♀ ovary granular, 20.5 gm., August 28, 1962, MCT 2831; ♀ imm., 20.0 gm., September 14, 1962, MCT 2925; ♂ testis 7 × 5 mm., September 25, 1962, MCT 2928; ♂?, October 2, 1962, MCT 2983; ♀, November 27, 1962, MCT 3357; ♂ testis small, December 1, 1962, MCT 3405; ♂ testis minute, December 2, 1962, MCT 3420; ♂ testis small, December 1, 1962, MCT 3434; ♂ testis small, November 30, 1962, MCT 3439; ♀, April 26, 1962, ADG 63; ♂, July 7, 1963, ADG 170; ♂, July 7, 1963, ADG 171; ♂, July 8, 1963, ADG 176.
This species commonly fed in the shade trees (Trema orientalis), along with other species of bulbuls. I occasionally saw individuals in primary forest.
Criniger bres gutturalis (Bonaparte): Olive White-throated Bulbul.—Specimens, 25: Cocoa Research Station: ♀ ovary regressed, 41.4 gm., July 27, 1962, MCT 2666; ♀, 46.0 gm., July 28, 1962, MCT 2672; ♂, 51.2 gm., July 31, 1962, heavy molt, MCT 2685; ♂ testis 4 × 3 mm., 52.6 gm., August 2, 1962, MCT 2710; ♂, November 27, 1962, MCT 3353; ♀, November 27, 1962, MCT 3354; ♀, June 14, 1963, ADG 138; ♀, July 8, 1963, ADG 172; ♂, July 7, 1963, ADG 173; sex?, July 11, 1963, ADG 190. 12 mi. N Kalabakan: ♀, October 16, 1962, MCT 3052; ♂ testis small, October 22, 1962, MCT 3127; ♂, October 24, 1962, MCT 3137; sex?, November 1, 1962, MCT 3190; ♀, November 2, 1962, MCT 3201; ♀, November 11, 1962, MCT 3250; ♂ testis small, November 13, 1962, MCT 3271; ♀, November 17, 1962, MCT 3301. Oil Palm Research Station: ♀, August 16, 1963, ADG 246; ♀ juvenal, August 19, 1963, ADG 253; ♀, August 23, 1963, ADG 256; ♀, August 28, 1963, ADG 264; ♂, August 28, 1963, ADG 270; ♀, August 28, 1963, ADG 271; ♀, October 4, 1963, ADG 293.
At the Cocoa Research Station this species was common and inhabited the cocoa and surrounding secondary forest. I found it to be common 12 miles north of Kalabakan.
Criniger ochraceous ruficrissus Sharpe: Brown White-throated Bulbul.—Specimens, 5: 5.5 mi. SW Tenom: ♀, December 21, 1962, MCT 3489; ♂ testis 3 × 2 mm., December 21, 1962, MCT 3490; ♂ testis 4 × 3 mm., December 21, 1962, MCT 3491; ♀, December 23, 1962, MCT 3518; ♀, December 25, 1962, MCT 3535.