227 
a Marigold, or some beautiful little syngenesious Jloiver ; the predominant colour 
of that class, no less than of the crests that represent them, being different shades of 
yellow. Now, it is a circumstance no less singular than remarkable, in conjunc¬ 
tion with what we shall presently state, that of between fifty and sixty birds pos¬ 
sessing this sort of crest, every one is purely insectivorous, that is, living entirely 
upon insects, which are caught, not by hunting, hut are seized only on their near 
approach. We have frequently 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 in¬ 
sects 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 restricted. We have fre¬ 
quently seen the Bentevi of Brazil, the most familiar as well as common species 
in that country, open and shut his fine yellow crest when merely occupied in 
watching for insects. This fact, joined with the considerations already mentioned, 
has more than once suggested to us the idea that these flower-like ornaments are 
occasionally used as snares to attract the attention of insects, so as to bring them 
within reach of being captured by a sudden dart.” 
This is curious and interesting, but Mr. Swainson omits to state what might, 
perhaps, throw a greater light on the subject—the trees principally frequented by 
these flycatchers, and the colour of their flowers. We should know this before 
we positively decide that the insects mistake the gold-coloured crests for flowers, 
particularly as syngenesious flowers, to which the crests are compared, do not 
grow upon trees, nor do trees produce them. We had marked various interesting 
passages for quotation on the sight, tongue, feet, and voice of birds, strikingly 
illustrative of the harmony perceptible in every department of nature, and the as¬ 
sociation of one tribe of beings with another ; but as we may have another oppor¬ 
tunity to dilate on these subjects we proceed to notice the second division of Mr. 
Swainson’s work, because suggestions arise there that we may not have a legiti¬ 
mate opportunity of remarking upon again. We would just mention, en passant , 
the observation that “ the powers of voice are certainly greater in birds, when their 
size is considered, than in any other class of animals, or even in man. This fact 
is established by experience and by comparative anatomy: we know that the crow¬ 
ing of a Cock may be heard at a far greater distance than the shout of a man, even 
had he the lungs of a Stentor ; and it may be even questioned whether the same 
remark may not be applicable to the full and sonorous warbling of the Thrush.” 
Mr. Swainson’s remarks on the progress of ornithological science are very ju¬ 
dicious, and deserve the particular attention of the student. His observations on 
ornithological bibliography are also deserving of notice, though here, we conceive, 
he has fallen into an error. On the very point where information would have 
been desirable he fails to give it, merely remarking that, “ in regard to European 
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