174 CARNEGIE INSTITUTION OF WASHINGTON. 



Owing to the probable necessity for abandoning the Tortugas as a 

 site for oiir principal laboratory, it seemed desirable to avoid intro- 

 ducing new investigators to this region, fearing that their work might 

 suffer should they be obliged to go elsewhere to complete it. More- 

 over, it seemed necessary to send Professor Harvey to Japan and 

 Professor Treadwell to Bennuda. The Department has found that 

 while it is relatively inexpensive to start a research, its legitimate 

 requirements are apt to draw heavily upon us as the work proceeds, new 

 and expensive experiments with costly apparatus often being required. 

 It is, however, the first aim of the Laboratory to maintain adequately 

 every research which falls under its auspices, and with the generous 

 support of the President and Board of Trustees it has been able to 

 carry out this ideal in an efficient manner. 



No hmitation should be attached either to the scope or character of 

 our research, provided it falls under the broad domain of marine 

 biology. Thus practical problems should interest us when such fall 

 within our scope and when we are exceptionally fitted to give aid to 

 their solution. For some years the Bahama Government has been 

 interested in the possible artificial culture of the sponge-beds of these 

 islands, and as extensive experiments have been conducted in this field 

 under the direction of Mr. E. Chase, at Sugar Loaf Key, Florida, His 

 Excellency Sir William Allardyce, K. C. M. G., Governor of the 

 Bahamas, was pleased to appoint, through the agency of the Marine 

 Products Board, Mr. H. C. Christie, who thus made a study, under our 

 auspices, of both the artificial and the natural sponge-beds of Florida in 

 order that he might report to liis Government upon their condition with 

 a view to improving the sponge-fisheries of the Bahamas. 



At Tortugas, Messrs. Bartsch, Bowman, Carj^, Goldfarb, Longley, 

 and Mayer continued the work they had commenced during or before 

 1915. Dr. Bartsch devoted a longer time than ever before to the 

 study of the cerions he has transplanted from the Bahamas, Porto Rico, 

 and Curagao to the Florida Keys. 



Dr. Bowman presents a report upon his ecological and physiological 

 studies of mangroves, which he conducted at Tortugas and at Miami, 

 Florida. 



For Professor Longley's researches, a new 26-foot naphtha launch, 

 the Darwin, having a glass bottom, and equipped to serve as a tender 

 in diving, was constructed during the winter of 1915-16 by our chief 

 engineer, Mr. John Mills. We also had made for his use an under- 

 water camera in order that he might take pictures of the reef fishes in 

 their natural habitat, viewing them as their enemies and associates 

 must see them. By means of these aids to research, Professor Longley 

 made a notable advance in his observations of the habits and colors of 

 fishes in relation to the appearance of their surroundings, proving that 

 protective coloration is a dominant factor in the ecology of reef fishes. 



