IN BORNEAN FORESTS [chap, i 



insect, returning to its perch to devour its quarry at leisure. It 

 also preys on small birds, showing a boldness hardly in keeping 

 with its lilliputian size. It certainly is one of the smallest of the 

 Raptores, being scarcely larger than a sparrow ; its plumage is of 

 a silky black with greenish sheen ; the under parts are white, and 

 altogether it is a finer bird than most of its allies. 



When the short twilight came on, it was not unusual to see 

 dark creatures jump noiselessly off from the bigger isolated trees, 

 perform a singular reversed parabolic flight, and alight on another 

 tree some thirty yards away, which they struck always lower than 

 the height they had started from, though they at once scrambled 

 up to about the same level. These were the great flying-squirrels 

 (Pleromys nitidus). The wide expansions of skin which extend 

 between the fore and hind limbs on either side are spread out when 

 they take their leap, and act as an admirable parachute. 



We soon found out that certain trees which appeared to be a 

 great attraction to birds were fig-trees, covered with ripe fruits not 

 bigger than a pea. These trees, which are named " Kayu ara," 

 are not only of many species in Borneo, but are all abundant ; their 

 fruits afford food to heterogeneous animals, but more especially to 

 birds. 1 The Fici of Borneo show quite a series of adaptations, both 

 in shape and size, to varied biological conditions, and well deserve 

 special investigation. 



The species of Ficus mentioned above as a great attraction to 

 birds — a Urostigma — had small leaves, and its branches came from 

 a large and very tall trunk, upon which, as an epiphyte, it had 

 originally grown. It spread over an immense area. Flight suc- 

 ceeded flight amidst its wide branches, but we had to wait patiently 

 until a bird showed itself clear to be able to shoot. If one fell the 

 others paid no attention. Many shots were tired without any 

 effect, on account of the great height of the branches, which were 

 for the most part beyond the range of our guns. The birds which 

 frequented these trees were mostly of brilliant colours ; amongst 

 them several species of barbet abounded (Chotorea, Xantholcema, and 

 Calorhamphus), of which we were able to collect many specimens. 



There may be exceptions, indeed, possibly many, but it appears 

 to me that birds which frequent the forests of tropical countries 

 and feed mostly on brightly coloured fruits, have a brilliant plumage 

 in which bright yellow and red predominate. Green is also a 

 frequent colour in the plumage of these birds ; and perhaps it was 

 originally not merely assumed in defensive mimicry, but as a sort 

 of instinctive sympathy with the surrounding predominant tint. 



1 ''Kayu" means tree in Malay, and is prefixed to the specific name of 

 any kind. The words Bunga (flower), Bua (fruit), Akar (root or liana), are 

 preposed in a similar manner. 



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