GALLERY.] NATURAL HISTORY. 93 
are generally of a green colour,, have long, slightly arched 
beaks, and long pointed wings; they associate in flocks, and 
fly like swallows, pursuing bees and wasps, which they 
prey on with impunity. They are only found in the Old 
World and Australia. 
In the other groups of this division the outer toes are 
generally shorter than the middle one, and they are only 
connected together to the base of the first joint. 
The Tenuirostral Birds have slender, compressed, 
and frequently arched bills, and their tongue is often 
divided at the tip into numerous filaments, and is used for 
sucking up the honey from the nectaries of flowers. The 
hind toes and claws are generally much larger than the 
rest. They are chiefly confined to warm climates. 
The family of Hopoes ( Upupidce , Case 43) have an 
elongated curved beak, with the nostrils covered with fea¬ 
thers, directed forwards. They have much the habit and 
appearance of the Crows. The Hopoes live on insects 
and fruit, and the Promerops upon the honey of flowers. 
The family of Sun Birds ( Nectarinidce , Case 43), from 
Africa and India, have the bill arched and finely toothed on 
the edge: the Hook-bill derives its name from the sin¬ 
gularly curved form of its beak. 
The family of Humming Birds ( Trochilidce Case 44) 
haye long, very slender bills, and long tongues, which they 
have the power of darting forward with great force, like 
the Woodpeckers. They prey chiefly on insects, and one 
genus (the Spider-Eaters), almost exclusively on spiders. 
Their small size and brilliant plumage have long rendered 
them celebrated. 
The family of Honeysuckers ( 'Meliphagidce , Case 45), 
which are peculiar to New Holland and the neighbouring 
islands, are generally of a dull black or olive colour, 
with compressed subulate beaks. 
The family of Creepers ( Certhiadce , Cases 46 and 47) are 
generally of a dull brown colour, and agree in many cha¬ 
racters with the Insectivorous Birds, especially the 
Warblers. Some have rounded tails, as the Anabates; 
others have the ends of the tail feathers and the webs on 
each side of them rigid like the Woodpeckers, and use 
them in the same manner to support their bodies while 
