102 



BULLETIN OF THE BUREAU OF FISHERIES. 



taken in the autumns of 1919 and 1920 the following information on this point was 

 brought to light : 



MM. 

 90 



80 



70 

 60 

 50 

 4-0 

 30 



1916 



1917 



1918 



1919 



1920 



Fig. 78. — Growth of 1916 offspring of domestic and wild parentage. Each lot was fed one 

 winter and selected for large size in the fall of 1917. — — — , Offspring of 1909 

 domestic stock; , offspring of original Carolina wild brood stock. 



SPACE REQUIREMENT. 



The 191 7 brood had two lots of ioo each chosen from it in 1919. One of these lots, 

 with average measurement of 52.5 mm., was placed in a large so-called fish pool which 

 measured 38 by 24 feet. The other lot with average measurement of 60.1 mm. was 

 placed in a small pen with dimensions of 29 by 12 feet. Observations on the growth of 

 the two lots have been as follows : 



