In this sentence, what part of speech is the word in bold?

the opening notes of the song caught my ear.

i'm not sure about this, can anyone ?

d.) then bernice winced as marjorie tossed her own hair over her shoulders and began to twist it slowly into two long blond braids until in her cream-colored negligée she looked like a delicate painting of some saxon princess. fascinated, bernice watched the braids grow. heavy and luxurious they were, moving under the supple fingers like restive snakes—and to bernice remained this relic and the curling iron and a to-morrow full of eyes.