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use of these glands, probably the greater number of physiologists and 
ornithologists believing that the organs, as the name implies, are 
for the purpose of secreting an oleaginous fluid, with which the bird 
lubricates its feathers. Many, on the contrary, are of opinion that 
these glands do not serve for such a purpose, among the latter may 
be included many practical ornithologists; I need only mention the 
name of Mr. Waterton, and it was in consequence of reading the 
following extract from his ‘ Essays on Natural History,’ 1844, p. 130, 
that my attention was specially directed to the subject ; and during 
the last few years I have weighed these glands, and taken drawings 
of them in many birds, British and foreign, that I have dissected. 
Mr. Waterton, among the reasons he gives for his belief that 
the glands in question are not used for the purpose of lubricating the 
feathers, says, in the work above referred to, “ Again the oil-gland 
in most water-fowls is covered with a thick tuft of down, not move- 
able at pleasure ; this tuft would prove an insurmountable obstacle 
to the transfer of matter from the gland through the medium of the 
bill. If for the purpose of lubricating the feathers, it would not 
have been granted by the Creator to one bird, and denied to another.” 
Mr. Waterton goes on to mention a Kestrel struck down by light- 
ning, in which the orifice of the gland was covered with a tuft of 
down, which had the exact appearance of a camel-hair brush, which 
= effectually impede the transfer of oil from the gland to the 
ill. 
As I shall not have space to quote other authorities, I may as 
well answer Mr. Waterton at once. As regards the absence of the 
glands, I suspect it is of very rare occurrence. I have never failed 
to find them, except on one occasion in a young Ostrich, and here 
they may have escaped my notice. In others of the Struthionide 
that I have examined I omitted to look for them, my attention not 
having at that time been directed to the subject. If they are absent 
in any bird, a ready explanation, I believe, will be afforded by its 
peculiar habits or locality. 
As for any impediment offered by the tuft of down to the egress 
of the oil, it is the most beautiful contrivance to effect this very 
object that can be imagined; as any one may determine by press- 
ing these glands in any of our poultry, especially in the ducks, when 
the tuft spoken’ of becomes saturated with oil, and serves as a kind 
of sponge, from which the bird with its beak, sometimes with its 
head, can obtain the fluid. To speak in a plain manner, every bird 
carries not only a grease-pot in its tail, but most of them have also a 
brush in addition to this appendage. 
But let any visitor to the Society’s Gardens watch the Pelicans 
when they have had their bath ; the birds, after soaking their fea- 
thers, dry themselves by flapping their wings; during this process 
the beak is frequently applied to the nipples of the glands, which, in 
this bird, are so large that they can readily be seen at some distance; 
the beak is then carried to various parts of the plumage, and the 
feathers are well-smoothed and oiled. The crown of the head, too, is 
often placed upon the nipples, and in this manner other parts are 
