A THEORY OF BIED& NESTS. 241 



diops of Tern ate. In others the band is rufous in the 

 female, as in several of the American species ; while 

 in Dacelo gaudichaudii, and others of the same genus, 

 the tail of the female is rufous, while that of the male 

 is blue. In most kingfishers the nest is in a deep 

 hole in the ground ; in Tanysiptera it is said to be 

 in a hole in the nests of termites, or sometimes in 

 crevices under overhanging rocks. 



2. Motmots (Momotidae). In these showy birds the 

 sexes are exactly alike, and the nest in a hole under 

 ground. 



3. Puff-birds (Bucconidae). These birds are often 

 gaily coloured ; some have coral-red bills ; the sexes 

 are exactly alike, and the nest is in a hole in slop- 

 ing ground. 



4. Trogons (Trogonidsa). In these magnificent birds 

 the females are generally less brightly coloured than the 

 males, but are yet often gay and conspicuous. The 

 nest is in a hole of a tree. 



5. Hoopoes (Upupidse). The barred plumage and 

 long crests of these birds render them conspicuous. The 

 sexes are exactly alike, and the nest is in a hollow tree. 



6. Hornbills (BucerotidaB). These large birds have 

 enormous coloured bills, which are generally quite as 

 well coloured and conspicuous in the females. Their 

 nests are always in hollow trees, where the female is 

 entirely concealed. 



7. Barbets (Capitonidae). These birds are all very 

 gaily-coloured, and, what is remarkable, the most bril- 

 liant patches of colour are disposed about the head and 



