I visited these barrows today there are 5 in a row with a common bank surrounding them. The bank is probably not ancient, it is typical of the C.18. Norman Quinnell thinks they are confluent bell barrows.
They are sized from west to east as follows:
1- 24 yards by 5 feet high
2- 20 yards by 5 feet high
3- 24 yards by 61/2 feet high
4- 20 yards by 6 feet high
5- 30 yards by 7 feet high
This information is from L.V.Grinsell's Somerset Barrows Part 1: West and South.