State Convention—Geological survey. 327 
with the well informed, may be illustrated by the following: I 
examined the digestive organs of an oriole and found, among other 
things, fragments of a beetle termed cincindela. I afterward saw 
a cincindela capture and devour another small carnivorous 
beetle. This beetle lives upon some other insect. Possibly it 
may also be carnivorous, but, sooner or later, in the series of 
victims, we shall probably find an insect that lives upon some 
s 
form of vegetation. Now the whole series depends upon the 
nature of this last term. If the vegetation is noxious, then the 
insect living upon it is our friend, and the one that preys upon 
him is our enemy, and the bird that preys upon him again is our 
friend. But if the vegetation is valuable, then it is just the 
reverse. But the case is not so simple even as to this. The 
The ori.ole lives upon other food than the cincindela, and the 
cincindela, on its part, does not chiefly live upon carnivorous 
beetles. The food of birds also varies more or less with the 
season, and that of insects with the state, whether larval or 
perfect. This case may be taken to illustrate the present state 
of the whole question; the something that we do know and the 
something that we do not know on this important subject. That 
which agriculture demands of zoological science is a list of 
mammals, birds, reptiles and insects that are our friends, and of 
those that are our enemies, and sufficient information concerning 
them to indicate how they may be fostered on the one hand or 
exterminated on the other. We have cats and dogs to prey upon 
troublesome mammals. Why not have cats and dogs among 
the insects for a similar purpose in their order of the animal 
kingdom ? 
The observations of the past summer have not been as numer¬ 
ous as could be desired, owing to the pressure of the more strictly 
geological work, but have been directed by the foregoing consid¬ 
erations. They relate chiefly to the food of birds and insects. 
The former were ascertained by examining the contents of the 
digestive organs, noting the time of day, as well as the day of the 
month. 
Of the birds examined, 46f per cent, were found to be exclu¬ 
sively insectiverous, while only 6f per cent, were found to be ex- 
