REPORT OF COMMISSIONERS OF INLAND FISHERIES. 105 



cut into small pieces about an eighth of an inch in diameter, and one 

 of these pieces placed in each jar. 



In order to determine to what extent the lobsters might have 

 derived food from the copepods and other organisms which could 

 get into the jars, one group of lobsters was retained as a control. 



These lobsters were kept under exactly the same conditions i:s 

 all the other lobsters, except that they were not fed, their only source 

 of food being the organisms which may have gotten into the jars 

 from the outside. That the amount of food thus derived from 

 external sources must have been very small indeed is clearly dem- 

 onstrated in the results about to be presented. 



Observations were made twice a day, and a record kept for the 

 date of moult for each individual. Occasionally a lobster was 

 moulting at the time of observation, but usually the moult had 

 occurred during the interval between two successive observations; 

 in this case the date of the first observation after moulting was 

 recorded as the date of moult. 



b. Results. 



The results of these experiments have been tabulated in the fol- 

 lowing form. By "moulting period " is meant the number of days 

 intervening between the third and fourth moults. Since in these 

 experiments both the age and size of the lobsters, and the tempera- 

 ture of the water, were practically the same for each group of lobsters, 

 the length of this "moulting period" may be regarded as a fairly 

 accurate indication of the effect of the different foods upon the rate 

 of growth, 



14 



