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Recent Literature. 
107 
and vine chafer was compensated by a general diminution of the ratios of 
all the other elements, and not by the neglect of one or two alone. If the 
latter had been the case, the criticism might easily have been made that 
the birds, in helping to reduce one oscillation, were setting others on foot. 
“3. The fact that, with the exception of the indigo bird, the species 
whose records in the orchard were compared with those made elsewhere, 
had eaten in the former situation as many caterpillars other than canker 
worms as usual, simply adding their canker worm ratios to those of other 
caterpillars, goes to show that these insects are favorites with a majority 
of birds.” 
We notice the unexpected fact respecting Fringillidce , that only 7 per 
cent of the food of 47 individuals of this “seed-eating” family, consisted 
of seeds, insects making up all but 2 per cent of the remainder. The 
canker worms alone made 40 per cent. But in this case it must be re- 
membered that the circumstances were highly exceptional. 
We trust Professor Forbes will not desist from his good work. Such 
exact data as these are just what is required for the solution of the general 
problem which is offered by the relations of the bird-world to agricul- 
ture. — E. C. 
Economic Relations of Birds again.* — Upon the heels of Prof. 
Forbes’s paper, but since the foregoing notice was penned (else the two 
contributions to the same subject might have been profitably considered 
together), comes the very elaborate result of Prof. King’s examinations of 
the food of birds in its bearing upon our agricultural interests. The ques- 
tion,— one of great economic importance, — seems to be only of late 
brought forward with sufficient prominence ; and it is evident from what 
these two investigators have accomplished, that our ornithologists have 
hitherto taken it up, if at all, only after methods entirely inadequate to its 
solution. Observations have usually been no more than incidental to our 
study of the habits of birds, instead of being sufficiently prolonged, exact 
and systematic to yield sound results. Prof. King’s field-work, we are 
informed, was commenced in 1873, and is apparently' only just concluded 
— his attention during this long period being steadily and rigidly directed 
to discovering what and how much food Wisconsin birds eat, with the view 
of classifying these birds in certain categories — primarily those beneficial 
to or injurious to, man in economic relations. This is certainly a worthy 
devotion, undertaken in truly scientific spirit, and carried out with an 
earnest purpose. It should go far toward accomplishing the desired result, 
— though we fear the problem is too* intricate, involving too many un- 
known quantities, to be solved, perfectly by never so many tabular state- 
ments of contents of birds’ stomachs. We suspect that the general equation 
reduced to its simplest practical terms will prove in the end to be, that the 
fewer birds of all kinds killed the better for us. 
* Economic Relations of Wisconsin Birds. By F. H. King. Wisconsin Geologica 
Survey, Vol. I, chap, xi, pp. 441-610, figg. 103-144. Roy. 8vo. 
