TAKING A ZOOLOGICAL CENSUS, 25 
or of predatory animals as checking its increase—we shall surely 
have acquired some valuable facts bearing upon its existence, and 
thus be enabled to judge with less chance of error respecting its 
preservation as a “ favoured race.”’ I am well aware that, in urging 
these remarks, I am laying myself open to the charge of Utopian- 
ism—and justly so, were I for a moment to deceive myself or to 
attempt to deceive others with the hope that such observations as 
I am advocating could be satisfactorily made, except in very few 
instances. But with these very few instances I am prepared to 
be content, at all events as a first step; for, if I mistake not, they 
would speedily be found of service, and the desire to extend them 
would as speedily grow. 
Now as to the method by which these suggestions may be put 
in practice. It is plain that here lies the chief difficulty, and I 
only approach it with great caution. It may be at first sight not 
unnaturally objected, that the difference between personal powers 
of observation, which I have before mentioned, and the existence 
of which no one can doubt, will be as insuperable when these ob- 
servations are represented in numbers as when they are expressed 
in words. I trust, however, that the Society will give me credit 
for asserting, on the strength of a somewhat protracted trial, that 
this objection is unfounded. I do not desire at present to go into 
particulars. I will merely state that I have found that, with com- 
paratively little trouble, a sufficiently accurate account of the ap- 
pearance, not only of every species of bird, but, with respect to 
many species, of every individual bird may be kept; and I do not 
see any reason why the same principle should not be extended to 
other groups of the animal kingdom. Indeed, I think that zoolo- 
gists have only to apply themselves to the task, each in his own 
district, to accomplish what is wantel. So far the matter is easy ; 
and were it only required that the numbers seen should be polled, 
no particular obstacle presents itself. But the real hindrance I find 
in what I may perhaps be allowed to call the “ disturbing forces,” 
which must be duly appreciated before the returns from different 
localities can be reduced to a common standard for comparison. 
Herein the zoologist must avail himself of the help of the geolo- 
gist and the botanist; and therefore have I thought it expedient 
to introduce the subject of this paper to the Linnean Society, a 
body so fully competent to deal with the mixed questions which 
must arise from its consideration, and with which I freely acknow- 
ledge my utter inability to cope. But I may also add that it is 
my intention immediately to pursue the matter further as regards 
