Section 26. Whoever maliciously gathers up or retains or maliciously aids in gathering up or retaining bills or notes of a bank or banking company, current by law or usage in the commonwealth, for the purpose of injuring or impeding the circulation or business of such bank or banking company, or of compelling it to do any act out of the usual course of its business, shall be punished by a fine of not more than five hundred dollars or by imprisonment for not more than two years; and in the prosecution of any such crime it shall not be necessary to set out and describe each bill, but it shall be sufficient to aver and prove any amount of the bills of any bank which have been so gathered up or retained.