ART. 3. TERTIARY CRINOID FROM WEST INDIES SPRINGER. 5 



a notable addition to tlie extremely small number of Tertiary crinoids 

 that are known. When we consider the vast extent of Eocene and 

 Miocene sedimentaries of marine origin in Europe, Asia, Africa, 

 Aus'tralia, the United States, West Indies, Central and South Amer- 

 ica, many of them tliousands of feet in thickness and richly fossil- 

 iferous, abounding in crustaceans, corals, mollusks, and other or- 

 ganisms everywhere associated with crinoids, in ages preceding the 

 Tertiary as well as in the present seas, it is remarkable how few are 

 the remains of crinoids which they have yielded. About 40 species, 

 embraced in 8 or 9 genera, will cover all that have been described, 

 most of them from very imperfect material, such as isolated colum- 

 nals of pentacrinites and centrodorsals of comatulids, among which 

 are doubtless a number of synonyms. Well-preserved specimens, 

 such as are so frequent in the Jurassic and Cretaceous, are almosb 

 unknown in the Tertiary, about all we know of the crinoid life of 

 that age being derived from the fragmentary remains above men- 

 tioned, and even these are of rare occurrence. 



Of the restricted number of species hitherto known, only a single 

 one has been derived from American rocks, namely, the cup of a 

 small comatulid belonging to the Thalassometrinae from the Eocene 

 of North Carolina, described by Emmons^ as Microcrinus conoidens. 

 A few other fragmentary remains, not hitherto noted or described, 

 occur in the same beds, and specimens of a species of a comatulid, 

 Nemaster, have been found in the Eocene of South Carolina — all 

 fragmentary and extremely rare amid a profusion of other fossils. 

 Therefore the present species coming from the West Indies is 

 the first stalked crinoid of Tertiary age to be described from the 

 Western Hemisphere. To it will be added another occurrence prob- 

 ably of the same genus, from the island of Tierra del Fuego, which 

 Doctor Bather informs me he will shortly describe. 



Eecent investigations in the West Indies and Panama * have shown 

 an extraordinary development of marine Tertiary formations, espe- 

 cially in the Plaitian and Dominican Republics, which in places 

 aggregate as much as 1,200 to 2,400 meters in thickness, in many 

 places filled with fossils. Yet out of the extensive collections made 

 during these researches and those previously made by other geologists 

 the 24 fragments upon which this species is based, from a single lim- 

 ited locality, represent all the fossil crinoid remains that have been 

 reported from the West Indies and adjacent lands, a region in the 

 waters of which they are now quite plentiful, amounting as thus 



"North Carolina Geological Survey, 1858, p. 311, figs. 246, 247. 



» Vaugiian, T. W.. Contributions to the Geology and Paleontology of the Canal Zone, 

 Panama, and geologically related areas in Central America and the West Indies, 1910. 

 Bulletin 103, U. S. National Museum. 



