KEPORT OF COMMISSIONERS OF INLAND FISHERIES. 109 



c. Discussion of Results. 



The results of these experiments show that the average length of 

 the moulting period of these fourth-stage-lobsters when fed on 

 different food, was as follows: 



Beef 11.2 days. 



Soft-shelled clam 11.3 days. 



Lobster's muscle 11.5 days. 



Shredded fish 11.7 days. 



Beef liver 12 .3 days. 



That all other food factors, except the particular food used in each 

 case, were practically eliminated in these results is demonstrated by 

 the fact that the average length of the moulting period for the 

 lobsters which were not fed was over twice as long, or 24.6 days. 



It is evident, therefore, that in these experiments the clam, beef, 

 lobster muscle, and fish were practically equal in food value, with 

 perhaps a slight advantage in favor of beef. The beef liver was the 

 least satisfactory — a rather unexpected result, for beef liver is suc- 

 cessfully used in trout hatcheries, and it was hoped it might prove 

 equally satisfactory for the lobster. 



Reviewing these results with reference to the choice of a food for 

 the lobsters, it is evident that lobster muscle and fish may be with- 

 drawn from further consideration. For these foods do not appear 

 to be any more nutritive than clam or beef, and the necessary sac- 

 rifice of adult lobsters in the use of the former and the oily char- 

 acter of the fish discredit their use for practical purposes. Liver 

 ■certainly is the cheapest food, but it seems to be the least nutritive, 

 and, moreover, it was observed to decay more quickly than other 

 foods. It appears, therefore, that the only remaining food tried 

 which might prove an improvement over the present use of the 

 soft-shelled clam is beef. 



In view of these results it was thought desirable to further test 

 the comparative value of beef and clam for the practical work of 



