Mass. Gen. Laws ch. 34 § 9
The commissioners shall hold meetings at the following times and places for their respective counties.
At Barnstable, the second Tuesday of April and October.
At Pittsfield, the first Tuesday of January, April, July and October.
At Taunton, the forth Tuesday of March and September.
At Edgartown, the Wednesday next after third Monday of May and the Wednesday next after the second Monday of November.
At Ipswich, the second Tuesday of April; at Salem, the second Tuesday of July; at Newburyport, the second Tuesday of October; at Lawrence, the last Tuesday of August; and the fourth Tuesday of December, at Ipswich, Salem or Newburyport, as they shall order at the preceding meeting.
At Greenfield, the first Tuesday of March and September and the second Tuesday of June and December.
At Springfield, the second Tuesday of April, the first Tuesday of October and the fourth Tuesday of June and December.
At Northampton, the first Tuesday of March, September and December and the Tuesday next after the second Monday of June.
At Cambridge, twice yearly; at Lowell, twice yearly; at Framingham, twice yearly.
At Dedham, the third Tuesday of April, the fourth Tuesday of June and September and the last Wednesday of December.
At Plymouth, the first Tuesday of January, the third Tuesday of March and the first Tuesday of August.
At Worcester, the fourth Tuesday of March, the third Tuesday of June, the second Tuesday of September and the fourth Tuesday of December.
They may by vote, specifying the time and place, establish other regular meetings within their county, and may also hold special meetings therein at such times and places as may be necessary. They may adjourn any regular or special meeting to any place within the county, and persons required to appear at, or processes returnable to, any such meeting, shall appear at or be returnable to the adjourned meeting.
Mass. Gen. Laws ch. 34, § 9