8o 



Papers from the Marine Biological Laboratory at Tortugas. 



Table 24 shows the decline in weight of two regenerating 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, 1912, 

 at Tortugas, Florida. One 

 of the specimens was a 

 disk deprived of both 

 stomach and mouth-arms, 

 and the other was a me- 

 dusa with the rim of its 

 bell cut off but with stom- 

 ach and mouth-arms intact; 

 thus both were regenerat- 

 ing new tissue. They were 

 kept side by side in one and 

 the same 6-liter aquarium 

 jar, and were thus sub- 

 jected to similar condi- 

 tions. The water was " 1 -i a 4 5 6 7 8 9 10 n 12 13 i4 15 le 17 is 19 

 changed once in every 24 Days x 

 hours. Diagram illustrating Table 24. 



1 Calculated according to formula y = 28-31 (i — 0.074)*. 

 ' Calculated according to formula y = 49.64(1 — 0.0512)*. 



Table 25 shows the decline in weight of the two halves of a disk of 

 Cassiopea xamachana without stomach or mouth-arms. One of these halves, 

 A, was starved in the diffuse daylight of the laboratory and the other, B, 

 in constant darkness, for 18 days, from February 28 to March 18, 1912, at 

 Montego Bay, Jamaica, at temperatures ranging from 24.5" to 28° C. The 

 two halves were maintained side by side in one and the same 6-liter glass 

 aquarium and the water was changed once in each 24 hours. 



