78 



Papers from the Marine Biological Laboratory at Tortugas. 



Table 21 shows the decline in weight of the two halves of a disk of 

 Cassiopea xamachana starved in the diffuse daylight of the laboratory at 

 Montego Bay, Jamaica, 

 from February 27 to March 

 18, 191 2, in water ranging 

 from 24.5° to 28° C. The 

 stomach and mouth-arms 

 of the medusa were re- 

 moved and the disk cut 

 into two nearly equal 

 halves, both of which were 

 maintained in one and the 

 same glass aquarium hold- 

 ing about 6 liters. The 

 water was changed once in 

 every 24 hours. 



9 10 11 12 13 14 15 16 17 18 19 

 Days X 

 Diagram illustrating Table 21. 



Table 21. 



1 According to the formula y ■• 

 * According to the formula y = 



iii.2S(i— 0.089)' 

 125-93(1— 0.092)* 



10 11 12 13 14 15 16 17 18 19 



Diagram illustrating Table 22. 



Table 22 shows decline 

 in weight of two regenerat- 

 ing specimens of Cassiopea 

 xamachana starved 19 days 

 in the dark, in filtered sea- 

 water, at temperatures 

 ranging from 27.5° to 30°C., 

 from June 26 to July 15, 

 1 91 2, at Tortugas, Florida. 

 One was a disk deprived of 

 its stomach and mouth, 

 arms, and the other was a 

 medusa regenerating its 

 bell-rim, but with stomach 

 and mouth-arms intact. 



