946 THE ENTOMOLOGIST’S RECORD. 
at the bird to see what it had got. We found it a material improve- 
ment in this respéct to have a hiding-tent with a narrow front and a 
wide back, as the side peepholes then gave us an extended angle of 
vision in front and enabled us to see birds approaching as well as 
actually at the nest. 
Rarely indeed did a negative, when put on the enlarging camera, 
enable one to say what the bird had really got. Birds besides brought a 
great many different kinds of food at once, and one got time to see 
certainly only a percentage. It was noticeable that we often caught 
birds with Lepidoptera in their bills when we were popping in and out 
of the tents, and the birds were very close and temporarily “froze.” 
In fact we found that the difficulties were often insurmountable, 
and if it be accepted that the very rigid proof the opponents of the 
theories seem to demand is essential to the satisfactory support of the 
theories, then | think it will require far more accurate and painstaking 
observation, and far more extensive observation, than any that has yet 
been attempted. 
However, I remind the opponents that, Mark Twain’s obiter dictum 
to the contrary notwithstanding, circumstantial evidence is often as 
good and sometimes even more difficult to rebut than direct evidence, 
and hundreds of people have rightly been suspended by their necks till 
they were dead on infinitely slenderer evidence than Mr. Colthrup and 
his co-thinkers demand. 
Sometimes, too, I regret to say, that the insistent demands that 
bread and butter matters make upon my brother’s and my own time, 
lead to the failure to record most interesting facts, since we often see 
interesting facts when moving about on business, and then the business 
crowds them out of our minds till they are recollected at a time when 
the sharpness of the mental impression has been degraded and we no 
longer feel it to be safe to make a note. 
In the observations below set out I have recorded all observations 
over the period covered by the notes of birds with food ; my reason for 
so doing is that it seems to me necessary that there should be no pick- 
ing and choosing of evidence, but that it should be viewed as nearly as 
possible as a whole, for the purpose of determining the relative habitual 
preying on the lepidopterous imagines. Hence food which is not even 
Insecta is noted. A reference to the calendar will show that the dates 
are Saturdays (when we usually get a couple or three hours to devote 
to field work) and Sundays. A reference to the meteorological records 
will show that about 50% of these days were unsuitable for observa- 
tions from one cause or another, and it must also be borne in mind 
that from October to March there is very little insect life available 
comparatively for our purpose. Hence the body of evidence below is 
more forcible than it seems at first sight, as a short calculation will 
show the available number of days on which we could observe. 
(To be continued.) 
