Why is lily bart distressed by the lines on her face

In "House of Mirth" by Edith  Wharton, Lily Barth is stressed about the lines on her face because she relied on her beauty to be successful, and she was worried that she was beginning to show signs of aging. She quickly dismissed the lines as just being tired.

- the heat nearly killed them that first summer.

mark twain, real name samuel langhorne clemens, was an american writer, humorist, entrepreneur, publisher, and lecturer. among his novels are the adventures of tom sawyer and its sequel, the adventures of huckleberry finn, the latter often called "the great american novel". wikipedia