124 REPORTS OX ixve;stigatioxs axd projects. 



of the water into nitrites and finally to expel the nitrogen from the sea in the 

 form of gas, thus depriving the surface waters of the ocean of nitrogen. 

 This relative scarcity of nitrogen in the tropical ocean accounts for the pau- 

 city of plant life in warm seas as compared with the conditions seen in tem- 

 perate regions, where great masses of Fiicus, etc., cover the rocks. 



Dr. Drew also showed that the formation of ammonia and final liberation 

 of nitrogen by this bacterium would leave the calcium free to combine with 

 the dissolved CO, of the ocean, thus causing a precipitation of calcium car- 

 bonate. The vast areas of chalky mud of the Bahama-Florida region and in 

 the coral regions of the tropical Pacific may have been formed in this man- 

 ner. This denitrifying bacterium appears to grow best in a moderate light 

 and to be most abundant at a depth of lo fathoms, below which it gives 

 place to another, non-denitrifying form, which appears to be characteristic 

 of the deep sea and is readily killed upon exposure to sunlight. 



His lucid report herewith presented demonstrates that these studies must 

 be undertaken with the best possible equipment of apparatus in Arctic, Tem- 

 perate, and Tropical oceans, and it is our hope that this most suggestive 

 research may be continued under the auspices of the Department of Marine 

 Biolog}'. 



Dr. E. Xewton Harvey continued his studies of the efficiency of alkalies 

 in penetrating living cells. He found that in KOH, XaOH, Sr(0H)2 the 

 muscles and nen'es cease to function before the alkali can penetrate the cells, 

 whereas in ammonia and the amines the cells are penetrated and lose color 

 before the muscles and nerves cease to function. With the exception of 

 trimethyl amine, the amines and inorganic hydroxides destroy nervous con- 

 duction before the muscles lose their power of contraction. He concludes 

 that a surface change conditions contraction and conduction. 



Dr. Har\-ey also studied the relation between penetration and cytolysis, 

 and he made an interesting obser^-ation upon the subject of nerve fatigue, 

 entrapping a contraction wave in a ring of tissue, through which it traveled 

 457 miles in 1 1 days. 



Dr. ]\Ierkel H. Jacobs carried out a study of the physiological reactions 

 and environmental relations of several species of protozoa which infest the 

 sea-urchin Diadema setosnm at Tortugas. 



Prof. William H. Longley studied the oecologv- of the varied animal life 

 inhabiting the gulf-weed, Sargassum, and it is to be hoped that he may con- 

 tinue this interesting subject. 



Mr. E. E. Reinke investigated the development and morphological rela- 

 tionship of the two forms of spermatozoa found in certain prosobranch 

 mollusks in Jamaica. 



Dr. T. Wayland \'aughan met with encouraging success in his studies of 

 the growth of reef corals, obtaining excellent photographs showing the an- 

 nual growth of the many colonies he is now rearing under natural conditions. 

 He also obtained bottom specimens from the quicksands between Rebecca 



