rock at Salem, Mass.; Atlantic shore changes; a raised beach at Marblehead Neck; the porphyries of Marblehead; geological survey of Essex County, Mass.; moulting of the lobster; malformation in lobster's claws; and biographical notices of George H. Emerson, Lucretia Crocker, Spencer F. Baird, Jules Marcou and T. T. Bouvé. Unfortunately, his style is confused, for he uses too many adjectives and subjunctive clauses, and rarely presents summaries of his conclusions. The complexity of his elaborate terminology also tends to deter the general reader, and he never sought to present his theories in simple language.
His productive period began immediately after the publication of Darwin's "Origin of Species" and ended just before the rediscovery of Mendel's law of heredity; thus he was one of the leaders in that active discussion of evolution during that speculative period which has now been superseded by direct experimental tests of the theory itself.
His last published papers are upon fossil cephalopods. In 1900, he completed the revision of the nautiloids and ammonoids for Eastman's translation of Zittel's "Handbuch der Paläontologie"; and after his death a manuscript upon "Pseudoceraties of the Cretaceous" was found lying upon his desk practically completed, he having written upon it on the last day of his life. This work was edited by Dr. T. W. Stanton and published as Monograph No. 44 of the U. S. Geological Survey in 1903. The last paper bearing his name was in cooperation with Professor James Perrin Smith upon the "Triassic Cephalopod Genera of America" and was published by the U. S. Geological Survey in 1905, consisting of 394 pages and 85 plates composed of photographic reproductions from the specimens themselves. For many years Hyatt was paleontologist upon the U. S. Geological Survey and these later papers were the results of his labors in this field.
He was elected to membership in the American Academy of Arts and Sciences at Boston in 1869 and was one of its vice-presidents at the time of his death. In 1875 he became a member of the National Academy of Sciences, and in 1895 of the American Philosophical Society of Philadelphia. He was also a foreign member of the Geological Society of London, and was associated with other leading scientific societies both at home and abroad. In 1898 he received the degree of LL.D. from Brown University, and he was one of the founders and the first president of the American Society of Naturalists.
His broad interest in all departments of knowledge, and his generous heart and kindliness to all about him caused him to be surrounded by a host of warm friends whose regard for him increased as years passed by. Thus it was that he was a prominent member of those remarkable social clubs of Boston which strove for the uplifting of humanity, and for the refining and perfecting of ideals of culture. Such were the Chestnut Street Club, a literary association numbering Longfellow,