118 OHIU EXPERIMENT STATION. 
harvest flies, and of beetles, the apple-worm when it leaves the apple, cut- 
worms, silk-worms” (Samuels); ‘‘Larve of Buibionide” (Packard) ; 
“ Larve of Dryocampa senatoria” (A.J. Cook). Glover also makes a plea 
for the robin, stating that as many as two hundred larvee of Bibio albi- 
pennis have ben taken from the stomach of a single robin. (Rept. Com. 
Agriculture for 1864, p. 441.) But as this species of insect is no longer 
considered injurious, the acknowledged great destruction of it brings no 
credit to the robin. | 
Having now given a.very incomplete synopsis of the work heretofore 
done on the feeding habits of the robin, I may proceed to an exposition 
of my own work upon this subject. The work was undertaken at the re- 
quest of the Horticulturist of this Station, Mr W J. Green, and has oc- 
cupied about one-third of my time during the season since April 1. I 
have not allowed more than five consecutive days during this time to pass 
by without killing one or more robins, sometimes as high as five or six 
per day, but averaging a little more than one perday. The great majority 
of the birds were killed on the Station grounds, about fitty being taken in 
other parts of the State. The stomach of each robin was removed while 
fresh, and the contents were at once placed in vials containing alcohol to 
preserve them in good order for future examination. The contents of 
each stomach were put in a separate vial. 
I have taken as great care as possible in the examinations of the food 
materials, sometimes spending thr-e or four hours upon a single stomach. 
For any errors in identification which there may be, I am, of course, re- 
sponsible. The determination of insect remains in the stomachs of birds 
is a very difficult and perplexing tark, and one which is not at all pleas- 
ant, since nearly all the material is in the very worst condition imagin- 
able, and mutilated and partly digested fragments of several species of in- 
sects being mixed up in utter comfusion. The elytra, mouth parts and 
tarsi of beetles are, of course, usually leit to tell their tales, as are also the 
harder parts of all other insects, snails, myriapods and the seeds of the 
various fruits; but the soft bodied larve and earth-worms are too often 
macerated almost beyond recognition. 
‘How to estimate the relative proportions of the various food matters 
found in the stomachs examined is a very important but rather difficult 
question. Upona slight consideration it becomes evident that we can 
not base our proportions upon the relative bulk of different materials. 
To illustrate, suppose we place on one side of the equation a blackberry 
and on the other enough chinch bugs to equal the bulk of the berry. It 
would obviously be very absurd to assume that the one counterbalances 
the other. Mr. King, in the article referred to, has considered this diffi- 
culty in the following words: 
