Studies of Tissue Growth 



445 



2.08 for the arms cut i cm. out. The table shows positively 

 that the nearer the disk the amputation is made the more rapidly 

 will the regenerating bud grow. 



The data from Ophiocoma riisei further substantiates the last 

 statement. Comparing the averages it is clearly seen, that the 

 arms cut off i cm. from the disk grow most rapidly, those cut 2 

 cm. out are next in rate, the stumps 4 cm. long grow new buds still 

 more slowly, and those arm-stumps 5 cm. long produce new tissue 



TABLE II 



Rates of arm regeneration at di^erent levels in the brittle-star, Ophiocoma riisei 



♦Regenerated portion broken and not measured. 



at the slowest rate. The buds in the latter case average only 72 

 per cent of the length of buds from the I cm. stumps. 



Miss King ('98) found that in the starfish Asterias vulgaris arms 

 were regenerated the more rapidly the nearer the base they were 

 removed. The brittle-stars behave in a similar manner. I know 

 of no exception to the rule that an appendage regenerates at a 

 faster rate the closer to the body the amputation is made. 



