EXTERNAL AN. TOMY. CONCEALED CRESTS. 37 
pleasure; but the principle of their construction is 
totally different, and is altogether peculiar. These 
crests are generally either of a bright yellow, red, or 
golden colour ; soroetimes, though very rarely, white.* 
If the feathers of the crown, which are not conspicu- 
ously elongated, are laid perfectly smooth, the crest 
does not appear, although its presence is sometimes 
indicated by a slight streak of the same colour. When 
the bird, however, is excited, the central feathers of the 
crown suddenly expand, radiate almost in a circle, and 
display what is often a most beautiful and striking 
ornament. The bright colours of the crest, in fact, are 
only at the roots of the feather, which are all tipt with 
the ordinary colour of the plumage ; so that when these 
are expanded, they are no inapt representation of the 
opening petals of a marigohl or some beautiful little 
syngenesious flower ; the predominant colour of that 
class, no less than of the crests which represent them, 
being different shades of yellow. Now, it is a circum- 
stance no less singular than remarkable, in conjunction 
with what we shall presently state, that of between fifty 
and sixty birds possessing this sort of crest, every one 
is purely insectivorous, that is, living entirely upon 
insects, which are caught, not by hunting, but are 
seized only on their near approach. We have fre- 
quently had occasion to advert to the fact, that all the 
tyrant flycatchers of Brazil never pursue their prey, or 
go out in search of it, by wandering about from tree 
to tree like other birds. They take their station on a 
particular branch, and there patiently wait, like a spider 
on its web, for such insects as come within range of 
a sudden dart. It is to this family of birds that the 
crests we have been describing are almost entirely re 
stricted. We have frequently seen the Bentevi of Brazil 
{Saurophagun sulphuratus Sw., Jig. 1 6 .) — the most fa- 
miliar, as well as common species, in that country — 
* As in two or three of the American tyrant flycatchers, and in the sub- 
genus Humicola Sw. North. Zuol. ii. p. 439. 
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