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TRANSACTIONS OF THE ILLINOIS 



most evident in the neutral or injurious elements, and amounts to little • 

 or nothing in the beneficial — ants being now but ten per cent, of the food, 

 caterpillars eleven per cent, and crane-flies thirteen per cent. ; while the 

 carabidje keep up to six per cent., curculios are reduced to two per cent., 

 spiders and myriapods to one and four per cent. These deficiencies are, 

 of course, made up by the appearance of small-fruits in the diet, averag- 

 ing twenty per cent, of currants and raspberries. These figures, strictly 

 construed, would indicate a balance against the bird ; and, taken by . 

 themselves, I don't see how they can even be forced into support of the 

 theory that the cat-bird is any peculiar blessing to the fruit-grower at 

 this time. 



In July the bird seems to become thoroughly demoralized. It 

 makes the heart of a friend sick within him to scan the columns of 

 averages. The ants drop to two per cent, of the food, the caterpillars to 

 three per cent., the carabidae rise to ten per cent., injurious beetles are 

 only one per cent., oethoptera but one per cent., spiders and thousand- 

 legs stand each at four per cent., and small-fruits climb to sixty-three 

 per cent. If all cat-birds ate like this at all seasons of the year we should 

 certainly class them with curculios and potato-beetles, as most grievous 

 pests. As far as these ten birds indicate anything, they seem to me to 

 indicate that the cat-bird in July is, to say the best of him, a blessing 

 pretty thoroughly disguised. 



Taking the whole three months together, adjusting and comparing 

 the values of his ten per cent, of ants, ten per cent, of caterpillars, twelve 

 per cent, of crane-flies, eight per cent, of carabidse, four per cent, of leaf- 

 chafers, three per cent, of curculios, two per cent, of oethoptera, three 

 per cent, of spiders and six per cent, of myriapods, I would estimate that 

 he has, at most, an unexpended balance of about seven per cent, of in- 

 jurious insects with which to pay for twenty-seven per cent, of fruit. 



THE BROWN THRUSH {Harporhyticus rufus, Cab.) 



The brown thrush is another bird too common to require descrip- 

 tion. Although it is reported by Baird, Brewer and Ridgway to reside 

 and breed all over the United States east of the Rocky Mountains, it is 

 in this State, like the robin and cat-bird, practically a strict migrant. 

 Mr. Nelson reports its occasional occurrence in Southern Illinois in mid- 

 summer. It reaches Bloomington about as early as the cat-bird, and 

 departs, I think, a little earlier. It is a shyer bird than either of the 

 preceding, andordinarily frequents the garden less. In the fruit season, 

 however, it partially masters its bashfulness, but even then it is more 

 difficult to detect in the act of thievery than the cat-bird or the robin. 

 The latter has no more conscience than a baby, and will slip a blackberry 

 down his throat, under your very eye, with a touching air of simple 

 innocence; but the brown thrush is sly enough — so sly that I have not 

 found any fruit-grower who could positively assert his guilt. I have had 

 no trouble in establishing his habits, however, and find him no more 

 honest than his fellows. (If I were reading this paper to birds I would 



