On the snow, among the outermost stems of the lilacs on one side of the dense thicket that they form was a female Downy with extended and quivering wings. About her hopped or rather danced a handsome male, showing the red on his occiput very conspicuously. He kept striking at her head with his bill and occasionally he held on for a few seconds, when the two birds fluttered about together and perhaps rolled over once or twice, closely united. At first I thought it an amatory encounter and I am still almost certain that the male attempted to secure sexual contact with the female once or twice. But if so it could not have been his primary or at least sole object. For he continued to peck her head even when she was lying almost motionless on the snow. For a time she seemed to be trying to escape and for fully two minutes her cries were piteous and incessant. At length he left her and flew up into an elm where he clung for a moment or two, making what seemed to me a very unusual display of the red on his occiput. Then of a sudden he swooped down on the female, who had meanwhile been cowering in the middle of a cluster of lilac stems, on the snow. Dragging her forth from this slight shelter into an open space, he attacked her again, this time with obvious fury, fairly raining a shower of blows on the back of her head. She seemed too weak to make any further attempt to escape and her cries, although continued, were so faint that we could only just hear them. I now realized for the first time that he was inspired by the _lust of killing_ and not by sexual ardor. It was very hard to refrain from rushing out and driving him away but I restrained the impulse, not being willing to interrupt a tragedy of such extraordinary, if repulsive, interest. It would have made no difference anyway, for, this final onslaught lasted only a very few seconds. During its continuance the male Downy seemed literally beside himself with rage. No Butcher Bird that I have ever watched has shown, while dealing with a Mouse or Sparrow, more murderous energy. After finishing the foul deed he left the female lying perfectly motionless and flew up again into the elm. We now went out and picked up the female. She was still living but unable to move. The [back] of her head was soaked in blood and her bare skull showed in places. She died a little later. I skinned her and preserved her skull which I have attached to the skin. It is _punctured in 10 or 12 places_. The bird was in normal condition physically with healthy-looking ovary the ovules undeveloped. The only injuries were to the skull.