152 NATURAL HISTORY [chap, xxvii. 



superficial examination the birds are identical, although 

 they have important structural differences, and cannot be 

 placed near each other in any natural arrangement. 



In the adjacent island oi" Cerani we find very distinct 

 species of both these genera, and, strange to say, these 

 resemble each other quite as closely as do those of Bourn. 

 The Tropidorhjnichus subcornutus is of an earthy brown 

 colour, washed with ochreish yellow, with bare orbits, dusky 

 cheeks, and the usual recurved nape-ruff. The Mimeta 

 forsteui which accompanies it, is absolutely identical in the 

 tints of every part of the body, and the details are copied 

 just as minutely as in the former species. 



"We have two kinds of evidence to tell us which bird in 

 this case is the model, and which the copy. The honey- 

 suckers are coloured in a manner which is very general in 

 the whole family to which they belong, while the orioles 

 seem to have departed from the gay yellow tints so 

 common among their allies. We should therefore con- 

 clude that it is the latter who mimic the former. If 

 so, however, they must derive some advantage from the 

 imitation, and as they are certainly weak birdsi^with small 

 feet and claws, they may require it. Now the Tropido- 

 rhynchi are very strong and active birds, having powerful 

 grasping claws, and long, curved, sharp beaks. They 

 assemble together in gi-oups and small flocks, and they have 

 a very loud bawling note which can be heard at a great 



