DEPARTMENT OF MARINE BIOLOGY. 187 



Professor E. Newton Harvey returned from Japan in January 1918, 

 whither he had gone upon a successful expedition to gather material 

 for further experiments upon the chemistry of light-production in 

 marine animals, and he gives herewith a second report upon this study. 

 Details of work accomplished by the investigators at Tortugas appear 

 in their special reports; but a brief summary of the scope of these 

 researches may be of interest. 



Dr. Paul Bartsch attempted to install his extensive breeding experi- 

 ments upon cerions not only at Loggerhead Key, Tortugas, but in a 

 specially constructed vivarium in his home in Washington, wherein the 

 temperature, degree of humidity, and other environmental factors are 

 made to imitate those of the Bahama-Florida region. He hopes thus 

 to acquire an insight into the life-history and breeding habits of these 

 snails and to supplement the breeding experiments to be reinstated in 

 Florida, the original attempt upon the Tortugas having failed, due to 

 the hurricane of September 10, 1919. 



At the Tortugas laboratory, in May, Dr. Joseph A. Cushman studied 

 the foraminifera of the region. Studies were made of the rate of move- 

 ment of the living animal in Iridia diaphana and other species, the 

 structure of the tests, and the cell contents. 



Collections were made of the bottom foraminifera in various depths 

 inside the lagoon and in the water immediately outside the reefs. 

 These will furnish material for a report on the foraminifera of the 

 shallow water of the region. Very little is known at present of the 

 foraminiferal fauna of the shallow water of the West Indian and 

 Florida regions. A comparison will be made of these recent collections 

 with those of the Coastal Plain Tertiary, in order to determine some- 

 thing of the ecological conditions under which these deposits were made. 



Professor Reginald A. Daly discovered that beach-rock, or coquina, 

 occurs only on shores subjected to heavy breakers. A promising 

 hypothesis to account for its formation, as indicated in his special 

 report, is that when sand is torn up from the bottom by storm-waves 

 and cast ashore it is necessarily charged with much organic matter, the 

 decomposition of which generates alkalies which through chemical 

 action cause the interstitial deposition of calcium carbonate, thus bind- 

 ing the grains of sand together and forming a rock-mass. 



From July 21 to September 16 Professor Daly studied the bed-rock 

 geology of Tutuila, Samoa, and made an extensive collection of the vol- 

 canic rocks of this island. Due also to the kindly interest of his Excel- 

 lency Commander Warren Jay Terhune, U. S.N., Governor of Samoa, 

 he was enabled to visit the islands of Anuu, Tau, Ofoo, and Oolosega, 

 in the U. S. S. Fortune, and later he spent a few days upon Upolu. He 

 will report in detail upon the lithology of these islands, but a pre- 

 liminary account of some of the more apparent conclusions are pre- 

 sented in his account published herewith. It may be noted that he 



