Both Mr. Humphrey's and His Inheritance and the Bellairs/Strickland adventure The Vengeance of the Witch-Finder (1993) feature a mysterious hedge maze containing hidden tombs at their center, both of which have curious domed tops:

     They turned left and plunged into a series of twists and turns. Before long, Lewis had no idea where they were or which way led back out of the maze. On either side, leafy green wall hemmed them in. Originally gravel had covered the paths between the walls. Grass and weeds had sprouted through the gravel. Now the brushy growth was knee high in places, and walking through it was like wading through water. (p. 26)
     The "building" that Bertie had mentioned was a small brick structure. It came up to Lewis' chest - about three and a half feet, he estimated. The brick was pale rd and crumbling. The top of the structure was concrete, with rounded edges so that rain would run off. In the very center of the top was a dome. It was about the size of Mrs. Zimmermann's largest mxing bowl, if the bowl were inverted to rest on its rim. This dome was made of concrete too, like the rest of the lid. (p. 44)

Strickland has said that including the nod to James was a "nice way of keeping continuity and giving two great writers a sort of moment on stage."

     It was a yew maze, of circular form, and the hedges, long untrimmed, had grown out and upwards to a most unorthodox breadth and height. The walks, too, were next door to impassable. Only by entirely disregarding scratches, nettle-stings, and wet, could Humphreys force his way along them; but at any rate this condition of things, he reflected, would make it easier for him to find his way out again, for he left a very visible track. So far as he could remember, he had never been in a maze before, nor did it seem to him now that he had missed much. The dankness and darkness, and smell of crushed goosegrass and nettles were anything but cheerful. Still, it did not seem to be a very intricate specimen of its kind. Here he was (by the way, was that Cooper arrived at last? No!) very nearly at the heart of it, without having taken much thought as to what path he was following. Ah! there at last was the centre, easily gained. And there was something to reward him. His first impression was that the central ornament was a sundial; but when he had switched away some portion of the thick growth of brambles and bindweed that had formed over it, he saw that it was a less ordinary decoration. A stone column about four feet high, and on the top of it a metal globe -- copper, to judge by the green patina -- engraved, and finely engraved too, with figures in outline, and letters.