CIRCLE OP THE TENOIHOSTRES. 149 
partaking both of the structure of the hoopoes and of the 
honeysuckers ; and both Cuvier, Lesson, Jardine, Selby, 
and James Wilson concur in believing that our Ptiloris 
paradiseus exhibits such a union : into which of these 
families, therefore, Ptiloris naturally enters, is a se- 
condary question, which need not here be discussed. The - 
oretically we might make use of this form, either to 
pass from the Paradise birds to the Melipluigidcf, or to 
Connect the latter with the Promeropicke, and thereby 
represent the aberrant circle as closed. The views, indeed, 
of the ornithologists above named, are aU in favour of 
the latter supposition, seeing that they have not, in every 
instance, separated Ptiloris from Epiniachus j the latter 
being universally considered as a hoopoe. Such appears, 
to us, an impartial statement of the difficulties which at 
present impede our knowledge of these three groups. 
(168.) Between the honeysuckers and the sunbirds 
the affinity is unquestionable ; and no one can doubt 
that the latter are followed by the humming-birds. 
The similarity between these latter and some of the 
small hoopoes is sufficiently strong to point out an 
affinity not very distant between them, so that there 
is every reason to believe the Ponuivostves are naturally 
disposed in one great circle. The Trochilida;, never- 
theless, arc one of those strongly marked groups in 
nature, which, if the term can be correctly applied, 
are, in one respect, isolated. The species are very 
numerous, and exhibit among themselves a great 
Variation in the structure of particular members ; yet, 
V'hen viewed ns a whole, they are stamped with such 
a peculiar character as to be recognised at the first 
glance. In other groups, ornithologists are perpetually 
deferring species to families which they closely resemble, 
hut to which they have no real affinity ; yet no one 
nan mistake a humming-bird, a hornbill, a toucan, a 
parrot, or a falcon ; nor is there hardly any species in 
these groups partaking so little of their respective 
typical characters, as to excite a doubt to which it 
truly belonged. Now, in applying these remarks to 
L 3 
