the first remains of reptiles found in the Palæozoic rocks of America. His studies in archæology also began in college.
To many readers, Prof. Marsh is best known in connection with his explorations in the Rocky Mountains, which he has crossed no less than eleven times on his various expeditions. His first visit to that country was a short excursion in 1868, which produced results of no little interest. From an alkaline lake in Wyoming he then obtained live specimens of larval Siredons, the remarkable change in which, occurring, under his own eye, after his return, called forth the paper "On the Metamorphosis of Siredon into Amblystoma." On this trip, too, a number of interesting Tertiary fossils were obtained from a well at Antelope Station, Nebraska, in the bed of an ancient lake, and at several other localities. The discoveries thus made indicated to Prof. Marsh the importance of this previously-unknown field, and he made preparations to undertake its systematic exploration. During the years immediately following his return from Europe, he had studied with much care the Cretaceous and Tertiary fauna of New Jersey; but it now became apparent to him that the fossil resources of these deposits were of much less importance than those of the West. In June, 1870, the first of the Yale Scientific Expeditions was organized and took the field, returning after an absence of five months, richly laden with fossil treasures. Over one hundred species of extinct vertebrates, new to science, were discovered on this trip. Most of these were from two Tertiary lake-basins before unknown. During the four years which followed, Prof. Marsh led other expeditions, which were scarcely less successful than the first, and the vertebrate fossils thus collected soon came to be reckoned by tons, instead of by hundreds or thousands of specimens. These various expeditions were attended with much danger and hardship, as the regions explored were often infested with hostile Indians, and explorations could be carried on only under the protection of a strong escort of Government troops. Prof. Marsh's early experience as a sportsman was also of great advantage, as the fact that he was the quickest and best shot in the expedition was soon acknowledged, and commanded respect from the soldiers and rough mountaineers who accompanied him. The expenditure of time which the leadership of these expeditions involved was, however, so great, that recently parties of trained collectors have been sent out, who pack the fossils on the ground and ship them to the Peabody Museum of Yale College, where they are examined by Prof. Marsh and his assistants. The expenses incurred in these various explorations have been great, and were mainly borne by Prof. Marsh, who has already contributed more than $100,000 to this work.
Among the most interesting of Prof. Marsh's recent discoveries are, a new mammal (Dryolestes); a new order of Reptilia (Stegosauria), and many new and gigantic Dinosaurs, all from the Jurassic of the Rocky Mountains, and the first found in this formation in this country.