354 



FRANCIS H. HERRICK 



The period illustrated in table VIII witnessed the first suc- 

 cessful attempts at molding, and the laying of the first strands to 

 fill the gap at the one open side, thus completing the wall of the 

 cup. At 10.26 a strip of shredded grape vine bark was brought 

 and placed against the nest-mass ; then straddHng the structure 

 she laid this across the open side, and by means of spiders' silk 

 and many rapid shuttle-movements of the bill, fixed first one 

 end and then the other, springing it slightly in the act. Another 

 strip was laid and secured in the same manner, with an ineffec- 

 tive trial at molding, and then another, when the attempt to mold 

 was successful, in the sense that the bird for the first time main- 

 tained her jDOsition. 



TABLE VIII 



Illustrating Building Activity op Red-Eyed Vireo. Second Day (May 31) 



At 4 p. M. on the second da 3^ the frame of this nest was com- 

 plete and was composed almost wholly of fine strippings of grape- 

 vine bark worked with spiders' silk. The latter was mainly 

 derived from the egg-cocoons of such species as nest on the 

 under sides of leaves or against the clapboards of houses. In 

 certain species the outer layer of the cocoon furnishes an easily 

 worked floss ; in others it is snow white and so soft and fine 

 as to be readily drawn into long and exceedingly delicate threads 



