There were a lot of "Boston & XXXX" railroads before the B&M gobbled up many shortlines in New England.
The Boston & Albany name came into use around 1870, and then became part of the New York Central system in 1914, though Yankee pride forced NYC to keep the B&A markings on their equipment.
Other "Boston &" railroads:
https://en.wikipedia.org/wiki/List_...ct_railroadsBoston and Albany Railroad
B&A NYC
1867 1961 New York Central Railroad
Boston, Barre and Gardner Railroad
B&M
1849 1885 Fitchburg Railroad
Boston, Clinton and Fitchburg Railroad
NH
1867 1876 Boston, Clinton, Fitchburg and New Bedford Railroad
Boston, Clinton, Fitchburg and New Bedford Railroad
NH
1873 1883 Old Colony Railroad
Boston, Hartford and Erie Railroad
NH
1863 1874 New York and New England Railroad
Boston, Hingham and Hull Railroad
NH
1880 1881 Nantasket Beach Railroad
Boston and Lowell Railroad
B&M
1830 1919 Boston and Maine Railroad
Boston and Maine Corporation
BM B&M 1963
Boston and Maine Railroad
B&M, BM B&M 1841 1964 Boston and Maine Corporation
Boston and Maine Railroad Extension Company
B&M
1844 1845 Boston and Maine Railroad
Boston and New York Central Railroad
NH
1853 1858 Midland Railroad
Boston and Portland Railroad
B&M
1839 1841 Boston and Maine Railroad
Boston and Providence Railroad
NH
1831 1972 Penn Central Transportation Company
Boston, Revere Beach and Lynn Railroad
1874 1940 N/A
Boston Terminal Company
BTCO NH
1896 1965 N/A
Boston and Winthrop Railroad
1881 1883 Boston, Winthrop and Shore Railroad
Boston, Winthrop and Point Shirley Railroad
1876 1883 Boston, Winthrop and Shore Railroad
Boston, Winthrop and Shore Railroad
1883 1891 Boston, Revere Beach and Lynn Railroad
Boston and Worcester Railroad
NYC
1831 1867 Boston and Albany Railroad
AND don't forget all of the TROLLEY lines, though I am not sure if they marked their mail differently.