the most productive material has been found in the foundations and cellar walls of buildings and in one instance the foundation wall of a large barn has been removed without disturbing the building, the abstracted rock being replaced with concrete as the work proceeded. Many hands have helped in the acquisition of this material: Messrs D. D. Luther, R. Ruedemann, C. A. Hartnagel, Jacob Van Deloo, H. C. Warden, Fred Braun and the writer, and while it may be difficult at the present to greatly enlarge these extensive collections, still they are only an index of the profusion of these forms of life in this pool.
Colony B, or the Buffalo pool, appears to have been quite closely confined to the quarry beds of the Buffalo Cement Company in the northern part of the city of Buffalo. It is from these quarries that the majority of the specimens widespread now through the museums of the world, has come. Formerly such specimens were available to any collector, but a few years ago the president of the company determined to place all specimens uncovered in the progress of quarry work in the possession of the Buffalo Society of Natural Sciences and by virtue of this laudable act that society possesses in the "Bennett Collection" a very remarkable array of these remains, which are specially noteworthy for the prevailing large size attained by the individuals. At the present time few Eurypterida are obtained from this historic locality and there is reason to believe that the boundaries of the pool have been approached, though remains of these creatures are found scattered at this geological horizon as far west as Bertie, in Ontario, the locality from which this waterlime formation takes its name. Like the Herkimer pool, that at Buffalo lies in the Bertie waterlime above the salt.
Colony S, or the Schenectady basin. This recent discovery (1910) of eurypterids in the Frankfort shale (Lower Siluric) is comparable to their occurrence at Otisville. These remains, usually in fragmentary condition, abound most freely in fine grained black shale intercalated between thick calcareous sandstone beds locally known as "Schenectady bluestone," but they also occur in the sandy passage beds between the two.
