DEPARTMENT OF MARINE BIOLOGY. 195 



The exceptional calms of June 1921 gave him a remarkable oppor- 

 tunity to extend his observations and obtain new photographs. 



Alfred G. Mayor studied the reactions of the small red ant so abund- 

 ant at Tortugas. It appears that when an ant finds some food (such 

 as a dead fly) it goes toward the nest and on the way meets others, 

 which become much excited and in turn communicate the excitement 

 to others. Then the original ant conducts her associates back toward 

 the dead fly. Contrary to the observation of Bethe, these Tortugas 

 ants do not follow the path of the original ant, but must be delib- 

 erately led by her back to the fly. An ant with abdomen sUt or 

 cut off appears to behave normally and goes from a fly it has found 

 towards its fellows of the nest, but these are not excited by it and do 

 not follow it back to the fly. The "finder" ant apparently has not 

 only a fair sense of the general direction back to the fly, but of the 

 distance as well, and having gone the right distance the swarm sud- 

 denly breaks up and reconnoiters in all directions, some of them find- 

 ing the fly, while many go astray. 



Professor Asa A. Schaeffer continued his study of marine amoebae at 

 Tortugas, very little being known of these minute forms, which are 

 exceedingly difficult to discover. He developed a number of cultures, 

 however, which provided him with a good supply of material, as appears 

 in his report. 



Professor A. L. Treadwell went to Montego Bay, Jamaica, in order 

 to extend his knowledge of the distribution of the Eunicidae for a 

 monograph upon these worms. In this study he has now visited 

 Tortugas, Bermuda, Porto Rico, Tobago, and Jamaica. 



The following papers have been presented during the year for pub- 

 lication by the Carnegie Institution. 



C. F. Silvester and H. W. Fowler on Samoan fishes. 



A. L. Treadwell. Annelids of Puget Sound. 



A. H. Phillips. Precipitation of metals in sea-water. 



E. N. Harvey. Luminous fishes from Banda. 



R. T. Chamberlin. Geology of the reefs of Tutuila. 



A. G. Mayor. Rose Atoll, Samoa. 



R. C. Wells. Carbon dioxide of Tortugas sea-water. 



Joseph A. Cushman. Foraminifera of Tortugas. 



The publication of papers has been delayed by various causes, but 

 the following, representing work performed wholly or in part under the 

 auspices of the Department of Marine Biologj'', were published: 



Bowman, H. H. M. 1920. Histological variations in Rhizophora mangli. 22d Report 



Michigan Academy of Sciences, pp. 129-134, pis. 9-12. 

 Cushman, J. A. 1921. Foraminifera from the north coast of Jamaica. Proc. National 



Museum, vol. 59, pp. 47-82, pis. 11-19. 

 Vaughan, T. W. 1919. Corals and the formation of coral reefs. Smithsonian Report 



for 1917, pp. 189-276, -37 pis. 



