William Diller Matthew was the eldest child of Dr. G. E. Matthew, of New Brunswick, an amateur geologist, who, by his great collections and excellent papers, added much to our knowledge of that part of Canada. Dr. Matthew was born on February 19,1871, in St. John, New Brunswick ; throughout his life he retained an interest in this town, visiting it yearly, except when abroad, and retaining his Canadian nationality during nearly forty years’ residence in the United States. Dr. Matthew was introduced to geological methods by his father, and sent at first to the small University of Halifax, whence in 1892 he proceeded to Columbia University as a graduate-student, there studying geology, mineralogy and metallurgy. He graduated Ph.D. in 1895. In that year he was selected by Professor H. F. Osborn, whose classes he had attended, as assistant in the department of Vertebrate Palaeontology in the American Museum of Natural History, New York. In this department he worked for thirty-two years, finally becoming Curator-in-chief of the division of geology, mineralogy and palaeontology.