Butterfield Bank shares fell 2 cents, or 1.43 percent, to close yesterday at $1.37.Some 189,487 Butterfield shares changed hands.Argus Group shares also declined, by $1.12, or 23.67 percent, to finish at $3.61. Some 2,700 shares traded.KeyTech shares rose 30 cents, to close at $6 as 10,183 shares traded.Overall the BSX closed down 25.86, or 2.27 percent, at 1,135.83.