220 BEACH GRASS 



of giving statistics as to the number of times the 

 young were fed per hour, or to calculate the 

 number of insects devoured — indeed I made no 

 notes of these important but rather dull facts — 

 but I would call attention to two very fundamen- 

 tal differences in the nesting habits of two such 

 similar birds. 



When the broods were young, the parents of 

 both species diligently removed the white sacs of 

 dejecta and dropped them at a distance, as is the 

 common habit of passerine birds. The habit was 

 continued during the entire residence of the 

 young tree swallows in their nest, but only while 

 the barn swallows were small. When the latter 

 had attained nearly adult stature and for several 

 days before they flew, they discharged their de- 

 jecta over the edge of the nest, whitening the 

 piazza floor below, but leaving the nest unsoiled. 

 In both cases the nest sanitation was perfect. 



The second difference in habit between the 

 two species is of considerable interest. The tree 

 swallow brood once launched into the world 

 was lost. As far as I know it did not again oc- 

 cupy its birthplace that season. Not so the barn 



