PROGRESS IN BIOLOGICAL INQUIRIES, 1935 419 



sudden appeaiance of large numbers of starfish is due to invasion 

 from other territories or to the increased propagation of the local 

 stock. Both field and laboratory Avork were carried out by Dr. 

 K. S. Rice, Charles F. Reppun, and George Mishtowt. 



There is no indication that starfish migrate during cold weather, 

 their distribution over the bottom of Buzzards Bay being more or 

 less constant with only small changes during the various seasons. 

 The greater concentrations were found on the New Bedford side 

 near the head of Buzzards Bay. The comparatively small number 

 of starfish now found in the bay is perhaps due to the combined 

 efforts of various town and State authorities who, with the help 

 of Federal relief grants, succeeded during the past 2-year period in 

 removing 173,300 bushels of starfish, or about 52 million adult 

 organisms. 



From laboratory experiments on the chemical control of this pest, 

 in which 22 various inorganic substances were used, it seems evident 

 that from every point of view^, copper sulphate is the most satisfac- 

 tory poison for killing starfish. In comparative ease of application, 

 low^ cost, small effective concentration, rapid diffusion, and quick 

 action, it is superior to other toxic substances that can be used in the 

 sea. Under laboratory conditions it was found to be effective in 

 great dilutions in killing starfish. Experiments were made to 

 develop a copper-glue compound jelly wdiich, placed on an oyster 

 bed, would slowh^ diffuse, creating for a short time a concentration 

 of copper sulpliate sufficient to kill starfish, finally clearing itself 

 completely, leaving none to injure the oysters. Earlier w^ork wdth 

 copper showed that its combination with a protein in order to pro- 

 duce a slow diffusion in water is lethal to starfish, but harmless to 

 oysters within the time limits chosen. However, further experiments 

 will be required in order to ascertain the most favorable concentra- 

 tion for practical purposes. 



During the summer laboratory studies were conducted on the feed- 

 ing habits and oviposition of the oyster drill, Urosalphix. It was 

 found that oysters, both young and adult, mussels, scallops, clams, 

 barnacles, and some other mollusks are all used by the drill as food. 

 Anomia, however, is never attacked. It appeared that barnacles 

 are the favorite food. 



Experiments in trapping drills on the rocky bottoms in the Woods 

 Hole section proved unsatisfactory because the barnacle-covered 

 rocks seemed to provide such an abundance of food that the drills 

 could not be attracted by bait. 



Laboratory observations indicate that there may be some correla- 

 tion between the number of egg cases laid, and the amount of food 

 available. 



Attempts to poison drills with copper sulphate were entirely 

 unsuccessful until dilute solutions were used that permitted the 

 drills to remain open and active. This was found effective as a 

 lethal agent when employed for a protracted time. Dilutions of 

 copper sulphate of 0.3 parts per mille were effective in 18 days. 



A survey of the Narragansett Bay, R. I., region w\as carried out 

 by J. J. Hellewell with the cooperation of the Rhode Island State 

 College which offered its laboratory facilities at Wickford, R. I., 

 Dr. Charles J. Fish, who assisted in inaugurating the project, and 



