Scott Seagrave was talking to Rosalie; she did not notice her husband.
After that, with easy nonchalance approaching impudence, he turned to his own neglected dinner partner, Sylvia Quest, who received his tardy attentions with childish irritation.

She didn't know any better.

And there was now no time to patch up matters, for the signal to rise had been given and Dysart took Sylvia to the door with genuine relief.

She bored him dreadfully since she had become sentimental over him.

They always did.
Lounging back through the rising haze of tobacco-smoke he encountered Peter Tappan and stopped to exchange a word.
"Dancing ?" he inquired, lighting his cigarette.
Tappan nodded.