Zoology 137 



No. 133. Papers from the Tortugas Laboratory of the Carnegie Institution of 

 YVashington. Vol. IV. Octavo, m+185 pages, 43 plates, 17 text figures. 

 Published 1910. Price $4.00. 

 This book contains the following papers, not sold separately: 



PRATT, HENRY S. Monocotyle floridana, a new Monogenetic Trematode. 9 pp., 1 1 figs. 

 LINTON, EDWIN. Helminth Fauna of the Dry Tortugas. II. Trematodes. .87 pages, 



28 plates. 

 VAUGHAN, THOMAS WAYLAND. A Contribution to the Geologic History of the 



Floridian Plateau. 86 pp., 15 plates, 6 text figs. 



Professor Pratt describes the only Trematode known to have a complete in- 

 testinal tract, the two intestinal trunks uniting to form a posterior caecum which 

 may open to the exterior by a terminal pore on the dorsal side of the animal. 



Professor Linton describes 46 new species of parasitic Trematodes from the 

 fishes and turtles of the Tortugas region. 



Dr. T. Wayland Vaughan traces the geologic history of the Floridian Plateau 

 from Oligocene to Recent time ; records the results of his exploration of the Flor- 

 ida Keys in the yacht Physalia, and presents a report on material from the sea- 

 bottom; he traces the several elevations and depressions, and calls special atten- 

 tion to the important role currents have played in shaping the contours of the 

 banks of southern Florida. 



No. 182. Papers from the Tortugas Laboratory of the Carnegie Institution of 

 Washington. Vol. V. Octavo, in-j-222 pages, 7 plates, 3 maps, 68 

 figures. Published 1914. Price $2.00. 

 This book contains the following papers, not sold separately: 



MAYER, A. G. In Memoriam, George Harold Drew. 6 pages, i plate. 



DREW, G. H. On the Precipitation of Calcium Carbonate in the Sea by Marine 



Bacteria, and on the Action of Denitrifying Bacteria in Tropical and Temperate 



Seas. 39 pages, 2 maps, 4 figs. 

 VAUGHAN, T. W. Preliminary Remarks on the Geology of the Bahamas, with Special 



Reference to the Origin of the Bahaman and Floridian Oolites. 8 pages. 

 VAUGHAN, T. W. Building of the Marquesas and Tortugas Atolls and a Sketch of 



the Geologic History of the Florida Reef Tract. 13 pages. 

 DOLE, R. B. Some Chemical Characteristics of Sea-Water at Tortugas, Florida. 



9 pages, i map. 

 GARY, L. R. Observations upon the Growth-Rate and (Ecology of Gorgonians. la 



pages, 2 plates. 



CLARK, H. L. Growth-changes in Brittle-Stars. 36 pages, 3 plates. 

 TENNENT, D. H. The Early Influence of the Spermatozoan upon the Characters 



of Echinoid Larvae. 12 pages, u figs. 



JACKSON, ROBERT T. Studies of Jamaica Echini. 24 pages, 21 figs. 

 JORDAN, H. E. The Spermatogenesis of the Mongoose; and a Further Comparative 



Study of Mammalian Spermatogenesis, with Special Reference to Sex Chromo- 

 somes. 20 pages, i plate, 9 figs. 

 OSBURN, R. C. The Bryozoa of the Tortugas Islands, Florida. 42 pages, 23 figs. 



The posthumous paper of George Harold Drew states that the fine unorganized 

 chalky mud of the Bahama Banks and Florida Keys is a precipitate due to bac- 

 terial action on the calcium salts present in solution in the sea-water. Also bacterial 

 denitrification of the sea-water is far more complete in tropical than in temperate 

 parts of the Atlantic and this explains the relative scarcity of plankton and plant- 

 growth in tropical seas, as was first determined by Brandt. 



Dr. T. Wayland Vaughan shows that the unorganized chalky mud which is pre- 

 cipitated by bacterial action may eventually become converted through accretion 

 into oolite in the manner explained by Linck. Dr. Vaughan also traces the history 

 of the several submergences and uplifts which have resulted in the formation of the 

 present Bahama and Florida reef regions. He states also that the lagoons and 

 sounds of this region are due to constructional geologic processes and not to 

 marine solution of limestone. The Barrier Reef of Florida, like that of Australia, 

 is growing along the seaward edge of a submerged platform which was submerged 

 and formed before the reefs began to grow upon it. Thus the reefs are a mere in- 

 cident and not a cause of the platform. 



Mr. R. B. Dole concludes that the water of the Tortugas lagoon and of Biscayne 

 Bay, Florida, contains no free carbon dioxide, and can not dissolve limestone by 

 virtue of its content of carbonic acid. This accords with Vaughan's conclusion 

 that the lagoons and sounds of southern Florida are filling up and are not being 

 dissolved out by the sea-water. 



