Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 160, § 197

Every railroad corporation having a terminus in Boston shall, upon the application of two hundred or more persons therefor, furnish on each week day a morning train in and an evening train out for distances not exceeding fifteen miles, or suitable cars attached to other trains, and reaching and leaving Boston at about six o'clock in the forenoon and afternoon, or at such hours as may be fixed by the department; and for such trains, shall furnish season tickets good once a day each way for six days in the week, at a rate not exceeding, for yearly tickets, three dollars a mile and for quarterly tickets, one dollar a mile.