5. Dolmens, signifying 'table stones' consisting of a number of menhirs called supports, placed close together to form a rectangle, open at one end and covered by one or more table stones.
6. Covered passages, two lines of parallel menhirs or supports covered by table stones.
7. Stone cists, composed of flat stones forming small closed chambers in the nature of stone coffins.
8. Tumuli, artificial mounds of earth called in England 'barrows' either oblong or round.
9. Galgals, artificial mounds formed of small stones.
The single standing stone or menhir is probably the oldest form
of all these monuments. Very rude peoples would soon naturally employ it for purposes of designation—to mark the grave of a chief or a spot become in some way sacred or important. Then a slab was placed across two or more uprights when an interment took place, and we have the beginning of the dolmen, which later developed into a more or less elaborate chamber, with or without vestibule or covered passage leading to it or auxiliary chambers connected with it; and finally the whole became covered with a mound of earth or small stones, and may have been surmounted by a menhir.
It has been said that the complete megalithic monument consisted of a stone chamber or dolmen covered with a mound, and the whole
