Gabriel Marcus Green was born in New York City, October 19, 1891. He attended the public schools there and graduated at the College of the City of New York in 1911. As an undergraduate he took high rank and was elected to the Phi Beta Kappa. He pursued his graduate studies in mathematics at Columbia University, where he came under the instruction of the eminent geometer, Professor Edward Kasner. His thesis for the doctorate was entitled: "Projective Differential Geometry of Triple Systems of Surfaces", and was a notable contribution to the subject. The degree was conferred on him in 1913.

Dr. Green returned to his college the next year as instructor in mathematics and in the fall of 1914 he became a member of the Department of Mathematics at Harvard. As a teacher he was successful from the beginning. Clear, interesting, vivacious, he imparted to his hearers an understanding of the subjects treated, which served as a firm foundation for further study. In research he was exceedingly productive, and in the brief span that was accorded him for his scientific labors he has given to the world a notable series of memoirs in his special field of projective differential geometry.

He was very fond of music. Although he had never had formal instruction, he had made himself a skilled pianist. His appreciation of music was extraordinary, and he had even essayed original composition.

His disposition was genial. He was emotional and sensitive, and at the same time sympathetic and unselfish. Ambitious and energetic, he demanded of himself a prodigious output. He entered into all the work of the Department with loyalty and devotion.

An attack of influenza was followed by pneumonia, and he died at the Still man Infirmary on January 24. We mourn him as a trusted friend