Nest-Building 151 



heard, but when another Robin or other strange bird tres- 

 passed on their preserve the alarm was promptly sounded, and 



Fig. 96. Baltimore Oriole hurriedly feeding her young before 

 all fear has been subdued and behavior is free. 



with shrill squeals of defiance the harmless visitor was assailed 

 and driven away. The intruder was taken unawares, and 

 seemed glad to escape from such fiery outbursts of pugnacity. 

 At each successive visit the characteristic molding and 



