246 



SCIENCE 



[N. S. Vol. XLIV. No. 1129 



(b) The Importance of Gravity Observations 

 at Sea on the Pacific: John F. Hayford, 

 College of Engineering, Northwestern Uni- 

 versity. 



(c) A New Method of Measuring the Accelera- 

 tion of Gravity at Sea: Lyman J. Briggs, 

 Bureau of Plant Industry, Washington, D. 

 0. 



(d) The Problem of Continental Fracturing 

 and Diastrophism in Oceanica: Charles 

 Schuchert, Department of Geology, Tale 

 University. 



(e) The Petrology of Some South Pacific 

 Islands and its Significance: Joseph P. 

 Iddings, Brinklow, Maryland. 



(f) In Relation to the Extent of Knowledge 

 Concerning the Oceanography of the Pa- 

 cific: G. W. Littlehales, U. S. Hydro- 

 graphic Office, Washington, D. C. 



(gr) Marine Meteorology and the General Cir- 

 culation of the Atmosphere: Charles F. 

 Marvin, U. S. Weather Bureau, Washing- 

 ton, D. C. 



(h) On the Distribution of Pacific Inverte- 

 brates: Wm. H. Dall, Smithsonian Institu- 

 tion, Washington, D. C. 



(i) The Marine Algae of the Pacific: W. G. 

 Farlow, Department of Botany, Harvard 

 University. 



0") The Pacific as a Field for Ethnological 

 and Archwological Investigation: J. Wal- 

 ter Fewkes, Bureau of American Ethnol- 

 ogy, Washington, D. C. 



{¥) Mid-Pacific Land Snail Faunas: H. A. 

 Pilsbry, Academy of Natural Sciences of 

 Philadelphia. 



(I) Some Problems of the Pacific Floras: 

 Douglas H. Campbell, Department of Bot- 

 any, Leland Stanford University. 

 The symposium contains a summary of some 



of the results obtained in past exploration of 



the Pacific and an outline of the importance 



to many sciences of further systematic and 



continuous exploration of the Pacific. 



15. Nervous Transmission in Sea-Anemones : 

 G. H. Parker, Zoological Laboratory of the 

 Museum of Comparative Zoology at Harvard 

 College. 

 There is evidence not only for the assump- 



tion of independent receptors, but of rela- 

 tively independent transmission tracts. A 

 first step in the kind of differentiation so 

 characteristic of the nervous organization in 

 the higher animals. 



16. The Responses of the Tentacles of Sea- 

 Anemones: G. H. Parker, Zoological Labo- 

 ratory of the Museum of Comparative Zool- 

 ogy at Harvard College. 

 The tentacles, in contradistinction to such 

 appendages as those of the arthropods and 

 vertebrates, contain within themselves a com- 

 plete neuromuscular mechanism by which their 

 responses can be carried out independently of 

 the rest of the animal. 



Edwin Bidwell Wilson 

 Mass. Institute of Technology 



SPECIAL ARTICLES 

 SOIL bacteria and phosphates 



Raw rock phosphate is by far the cheapest 

 source of phosphorus to apply to soils. It con- 

 sists chiefly of tricalcium phosphate, Ca 3 (PO,,) ! , 

 which is the most common form of phosphorus 

 in the great natural deposits. This phosphorus 

 compound is relatively insoluble in water, and, 

 for this reason, it has been argued by some 

 that it does not become available to plants ; but 

 long-continued field experiments, pot-culture 

 experiments, and farm practise have fully 

 demonstrated that this kind of phosphate does 

 become available for plant growth. 1 



The increased beneficial results obtained by 

 following the practise commonly recommended 

 of intimately mixing decaying organic matter 

 with the phosphate lead to the suggestion that 

 the action of the soil bacteria that decompose 

 organic matter might be an important factor 

 in the solution of the phosphate. 



It has been the common teaching that nitri- 

 fying bacteria require the presence of a free 

 base, such as lime or an alkaline carbonate, 

 but we have found that the bacterial action 

 produces acid phosphate and proceeds in the 

 presence of this acid salt. 



The importance of the action of decomposi- 

 tion products of the active organic matter of 



i See Circulars 181 and 186, Illinois Agricul- 

 tural Experiment Station. 



