Numerous biographies and monographs of Agassiz exist in many languages, a complete list of which is given in the last published 'Life of Agassiz,' by Jules Marcou (New York and London, 1896), and also in the 'Life of Agassiz,' by Charles F. Holder (New York, 1893). Complete lists of Agassiz's works are also given in these biographies, and these titles show how versatile was his taste and how deep and wide his research. His principal contributions to science are in French and Latin, but his most popular books appeared in English. These include 'The Structure of Animal Life,' 'Methods of Study,' 'Geological Sketches,' and 'Journey in Brazil,' the latter written with Mrs. Agassiz. His 'Contributions to the Natural History of the United States,' planned to be in ten large books, only reached four volumes. In his 'Researches concerning Fossil Fishes,' Agassiz expressed the views that made him a lifelong opponent of the Darwinian theories, although he was a warm friend of Darwin. Considering the demands upon his time as teacher, lecturer, and investigator, the excellence not less than the amount of the great naturalist's work is remarkable, and won such admiration that he was made a member of nearly every scientific society in the world. One of his favorite pastimes was deep-sea dredging, which embraced the excitement of finding strange specimens and studying their singular habits. Of his love and gift for instructing, Mrs. Agassiz says in her 'Life' (Boston, 1885):-- "Teaching was a passion with him, and his power over his pupils might be measured by his own enthusiasm. He was, intellectually as well as socially, a democrat in the best sense. He delighted to scatter broadcast the highest results of thought and research, and to adapt them even to the youngest and most uninformed minds. In his later American travels he would talk of glacial phenomena to the driver of a country stage-coach among the mountains, or to some workman splitting rock at the roadside, with as much earnestness as if he had been discussing problems with a brother geologist; he would take the common fisherman into his scientific confidence, telling him the intimate secrets of fish-culture or fish-embryology, till the man in his turn grew enthusiastic and began to pour out information from the stores of his own rough and untaught habits of observation. Agassiz's general faith in the susceptibility of the popular intelligence, however untaught, to the highest truths of nature, was contagious, and he created or developed that in which he believed." The following citations exhibit his powers of observation, and that happy method of stating scientific facts which interests the specialist and general reader alike. THE SILURIAN BEACH From 'Geological Sketches'