111 PROTECTIVE RESEMBLANCES AMONG ANIMALS 73 
Oxyrhopus formosus, both being found in many localities of 
tropical South America. 
What adds much to the extraordinary character of these 
resemblances is the fact, that nowhere in the world but in 
America are there any snakes which have this style of 
colouring. Dr. Gunther, of the British Museum, who has 
kindly furnished some of the details here referred to, assures 
me that this is the case ; and that red, black, and yellow rings 
occur together on no other snakes in the world but on Elaps 
and the species which so closely resemble it. In all these 
cases, the size and form as well as the coloration are so 
much alike, that none but a naturalist would distinguish the 
harmless from the poisonous species. 
Many of the small tree-frogs are no doubt also mimickers. 
When seen in their natural attitudes, I have been often unable 
to distinguish them from beetles or other insects sitting upon 
leaves, but regret to say I neglected to observe what species 
or groups they most resembled, and the subject does not yet 
seem to have attracted the attention of naturalists abroad. 
Mimicry among Birds 
In the class of birds there are a number of cases that make 
some approach to mimicry, such as the resemblance of the 
cuckoos, a weak and defenceless group of birds, to hawks and 
Gallinaceze. There is, however, one example which goes much 
further than this, and seems to be of exactly the same nature 
as the many cases of insect mimicry which have been already 
given. In Australia and the Moluccas there is a genus of 
honeysuckers called Tropidorhynchus, good sized birds, very 
strong and active, having powerful grasping claws and long, 
curved, sharp beaks. They assemble together in groups and 
small flocks, and they have a very loud bawling note, which 
can be heard at a great distance, and serves to collect a 
number together in time of danger. They are very plentiful 
and very pugnacious, frequently driving away crows, and 
even hawks, which perch on a tree where a few of them are 
assembled. They are all of rather dull and obscure colours. 
Now in the same countries there is a group of orioles, forming 
the sub-genus Mimeta, much weaker birds, which have lost 
the gay colouring of their allics, the golden orioles, being 
