344 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 3 



Experiment in Feeding English Sparrows 



The first lot of six sparrows was cauglit February 20. These were 

 not offered food imfortun'ately until the following day, as -the cage 

 described later was being constructed. The hairy covering of the 

 egg-cluster was removed by gently rubbing over cheesecloth, stretched 

 between two boards. The eggs were mixed with dough made of corn- 

 meal and water and used for food. The last of this lot of birds died 

 during the night of February 21. 



This proved an unsuccessful way of obliging the birds to eat the 

 eggs. After a bolus of the food was forced into the beak, and the 

 latter released in order that the bird might swallow, it would move 

 the tongue to and fro, ejecting most of the eggs. No parts of eggs 

 were found in the excrement or gizzard after the bird's death. This 

 showed that none were swallowed by them while in captivity. Similar 

 results were obtained from the second lot, which were captured ]\Iarch 

 6, and which died on the evening of March 7. 



A different method was pursued in the latter experiments to compel 

 the sparrows to swallow the eggs. They were inserted by means of a 

 dampened toothpick, to which the eggs adhered. The toothpick was 

 inserted well into the mouth and sometimes conveyed ten to fifteen 

 of these, after which the sparrow was given a swallow of water. In 

 this manner the birds were forced to swallow several eggs as is shown 

 by the table. 



One bird was captured March 27 and died March 29 ; the other two 

 April 10 and died April 11 and 12, respectively. In these experiments 

 half-pound candy boxes were used, while the first two lots of birds 

 were kept in a cage. It measured 8 inches square by 12 inches deep, 

 with fly screen top and bottom. In one side a hole, large enough to 

 admit the hand, was made and provided with a slide cover. By this 

 arrangement it was possible to remove them conveniently at feed- 

 ing time. It was decided that this cage was too large and allowed the 

 birds too much freedom to fly, so that they killed themselves by con- 

 stantly beating against the screens. The small candy boxes proved 

 more satisfactory. 



Approximately 356 P. dispar eggs were fed to the last three spar- 

 rows. One hundred and forty-two of these eggs or 40 per cent, were 

 found intact in the excrement. Seven of the 356 (2 per cent.) or 5 

 per cent, of the 142 that were passed intact hatched. One hundred 

 and thirty-five or 38 per cent, was the approximate number found to 

 be digested or partly so. Small pieces of chorion, which is indigesti- 

 ble, could usually be seen with the aid of a lens. Seventy-nine of the 



