SPAREOWS IN CAPTIVITY. 49 



he had secured all the uncovered seeds, he scratched in the sand for 

 the buried ones. When thus engaged he would give a quick jump 

 into the air, swinging his feet forward and then backward, scratching 

 the ground with both feet at once, and apparently with motionless 

 wings. 



During January and February, 1900, a series of experiments was 

 carried out to ascertain how far sparrows are responsible for the 

 dissemination of the seeds upon which they subsist. The only birds 

 available for these experiments were seven English sparrows, but the 

 conclusions reached are, in a measure, applicable to all sparrows. 

 The birds were fed seeds of different weeds, and all their droppings 

 were examined to ascertain the condition in which the seeds were 

 voided. The seeds of climbing false buckwheat and ragweed were 

 found to be thoroughly pulverized, although quite a number of small 

 fragments of the black, shiny seed coats of the former were found in 

 the droppings. This result was expected, since the birds crack these 

 seeds before swallowing them. The seeds of lamb's-quarters and 

 amaranth were' next tried. These, because of their small size and 

 hard structure, it was supposed would be swallowed whole and would 

 partially escape destruction in their passage through the birds' digest- 

 ive tracts. But such proved not to be the case. The birds cracked 

 them as they had the others. Halves of seed shells were found in the 

 seed cup, and many broken smaller pieces; and the droppings of the 

 birds showed no whole seeds, although some few empty split seeds 

 with the two half shells clinging together were found. Usually only 

 the finely pulverized dust of the seed coats was found in the fseces. 

 When the sparrows were not under experimentation they were fed 

 chiefly on millet, the grain of which is inclosed by two corrugated 

 siliceous glumes. These were similarly removed by the birds. No 

 whole seeds were found in the dung, and only an occasional small 

 piece of one of the glumes. The closely related seeds of pigeon-grass 

 (Choetocloa viridis) are inclosed by much stronger glumes, but when 

 these were fed to the birds the cracking of the grain and the remov- 

 ing of the glumes appeared to be just as complete as in the case of 

 the millet, and seemed as certainly to preclude smj possibility of sub- 

 sequent germination. 



Some experiments were made with the seeds of crab-grass {Pani- 

 cum sangumale). A well-known firm of seedsmen suggested to the 

 Department the probability that the English sparrow was respon- 

 sible for the occurrence of crab-grass in lawns and golf links sown 

 with pure seed of the finest brand. Much complaint was received 

 from buyers of lawn-grass seed because, after the seed was planted 

 and the turf well established, crab-grass appeared in it, often so thickly 

 as to necessitate plowing under the whole lawn. Two sparrows were 

 fed with 100 of the seeds. Instead of manipulating them as they did 

 the seeds of millet and pigeon-grass thej^ swallowed them whole, 



