98 SMITHSONIAN INSTITUTION 



of Stalked crinoids and comatulids known at the date of P. H. Carpenter's 

 monographs upon the collections of the "Challenger" expedition, there are 

 now known 142 genera and 576 species, of which 123 genera and 343 species 

 have been described by Clark alone; these are distributed among 20 families 

 and 8 sub-families. The crinoids, therefore, constitute one of the richest 

 and most varied faunas of the present seas, the extent and importance of which 

 will continue to increase; for, notwithstanding the great acquisitions of the 

 past dozen years due to the activities of numerous dredging expeditions main- 

 tained by different governments, the fact still remains that all these dredgings 

 represent only the imperfect gleanings of a few out of the 140,000,000 square 

 miles which the oceans cover. The number of crinoids existing in certain 

 localities is amazing; as many as 10,000 have frequently been brought up by a 

 single haul of the dredge. A. Agassiz * speaks of " a field of Rhisocrinus " 

 growing on the sea bottom in the West Indies. At Singapore 24 species of 

 crinoids have been taken within a radius of a few miles, a variety which is 

 surpassed by but few localities of Paleozoic crinoids. 



It is somewhat remarkable how meager are the remains of fossil crinoids 

 thus far known from other continents than Europe and America. A few 

 have been reported from the Andes in South America; some of Jurassic age 

 from China, from the islands of New Guinea, Misol and Roti, and from the 

 Arctic regions. An interesting" fauna, chiefly Carboniferous, has been de- 

 scribed by Ratte and by Etheridge from Australia; Ordovician, Silurian and 

 Devonian crinoids and cystids from India by Reed, and also a Carboniferous 

 species by De Koninck. A more remarkable Echinoderm fauna has been dis- 

 covered in the island of Timor, in the Dutch East Indies, some forms of which 

 have been described by Beyrich, by Bather, and by Wanner ; large collections 

 have been made in recent years by the Dutch geologists headed by Dr. G. A. F. 

 Molengraaff of Delft, and by Professor Wanner of Bonn. This fauna is said 

 to be Permian, but I feel confident that, as already suggested by Bather, it will 

 prove to be in part Lower Carboniferous. None of these outlying occurrences, 

 to my knowledge, have thus far yielded any specimens of true Flexibilia. 



The annexed table of Distribution furnishes a resume of the occurrence of 

 the Flexibilia throughout the recognized American time divisions and their 

 approximate European equivalents, as well as within the two continents. 



'Three Cruises of the U. S. Coast Geodetic Survey Steamer "Blake," etc., from 1877-1880 [1888], 

 p. 118. 



