Sentence:  On the way they pointed out the tennis court and the old summerhouse, a mock <WSD>"tholos</WSD>", Doric by way of Pompeii, and Stanford White, and (said Francis, who was scornful of this Victorian effort at classicism) D. W. Griffith and Cecil B. De Mille. 
Meaning of the word marked with <WSD> tags:  A dome, or domed building; a cupola.