Mary T. Browne is not mentioned in the provided text about Buckingham Browne & Nichols School.
The provided text details the history and notable alumni of Buckingham Browne & Nichols School (BB&N), an independent co-educational day school in Cambridge, Massachusetts. The school's origins trace back to 1883 with the founding of George Henry Browne's School, a college preparatory institution established by a Harvard graduate. Simultaneously, Jeanette Markham founded her school in 1889, which would later become The Buckingham School. These two institutions eventually merged to form BB&N. The text also highlights the school's athletic achievements, including its rowing team's victory at the Henley Royal Regatta in 1929 and successes in tennis. A comprehensive list of notable alumni from both the Browne & Nichols and Buckingham schools, as well as the merged BB&N, spans various fields including arts, sciences, politics, and athletics. However, Mary T. Browne is not listed among these alumni or mentioned in any other capacity within the provided information.