398 



fishes and reptiles, many of which can live for months without 

 food ; and also with that required by mammalia — a man, at this 

 rate, should eat about seventy lbs. of flesh a day, and drink five 

 or six gallons of water. The question immediately presents 

 itself, how can this immense amount of food, required by the 

 young birds, be supplied by the parents ? Suppose a pair of old 

 robins with the usual number of four young ones — these would 

 require, according to the consumption of this bird, two hundred 

 and fifty worms, or their equivalent in insects or other food daily 

 — suppose the pai-ents to work ten hours, or six hundred minutes, 

 to procui-e this supply ; this would be a worm in every two and 

 four-tenths minutes ; or each parent must procure a worm or its 

 equivalent, in less than five minutes during ten hours, in addition 

 to the food required for its own support. He was unable to 

 reconcile this calculation with actual observation of robins, which 

 he had never seen return to their nests oftener than once in ten 

 minutes. After the 3 2d day the bird had attained its full size, 

 and w\as entrusted to the care of another person during his own 

 absence of eighteen days ; at the end of that period the bird was 

 strong and healthy, with no increase of weight, though its featli- 

 ers had grown longer and smoother. Its food had been weighed 

 daily, and averaged fifteen dwt. of meat, two or three earth- 

 worms, and a small quantity of bread each day; the whole being 

 equal to eighteen dwt. of beef, or thirty-six dwt. of earth-worms ; 

 and it has continued to eat this amount to the present time. The 

 bird having continued, in its confinement, with certainly much 

 less exercise than in the wild state, to eat one-third of its weight 

 of clear flesh daily, he concludes that the food it consumed when 

 young was not much more than must always be provided by the 

 parents of wild birds. The food was never passed undigested ; 

 the excretions were made up of gravel and dirt, and a small 

 quantity of white semi-solid urine. 



He thought that every admirer of trees may derive from these 

 facts a lesson, showing the immense power of birds to destroy the 

 insects by which our trees, esjiecially our apples, elms, and lin- 

 dens, are every few years stripped of their foliage, and, often 

 many of them killed. The food of the robin, while with us, con- 

 sists principally of earth-worms, various insects, their larvce and 

 eggs, and a few cherries ; of worms and cherries they can pro- 



