26 BIRDS THROUGH AN OPERA-GLASS. 
After a few moments he would drop it, smooth 
his plumage, wheel about, whisk his tail, and per- 
form various other antics for the delectation of 
Mrs. Blackbird ; then he would suddenly dart off 
to see what the robins were about. 
“During the weeks that followed, through nest- 
making and incubation, the enmity between the 
blackbirds and robins never abated. They were 
ever wary and on the alert, and if 1t chanced that 
either party, returning to his home, happened to 
cross the ‘ Mason and Dixon’s line,’ the other was 
out of his nest in a trice to drive off the intruder. 
Sometimes I thought both parties courted these 
oceasions, though they would generally content 
