402 Charles Zeleny 
TABLE g—CassioPEA XAMACHANA 
Width of regenerated margin in millimeters 
FIRST REGENERATION SECOND REGENERATION 
0.5 0.8 
0.2 1.6 
0.2 
Average = 0.3 mm. | Average = 1.2 mm. 
In three individuals the first regeneration of a segment of the 
outer margin was compared with the second regeneration of a 
similar segment of the same animal. ‘The method differed for the 
three cases and the original article should be referred to for the 
differences. In all three cases the second regeneration is more 
rapid than the first. ‘The data are given in Table to. 
TABLE 1o—CassiopEA XAMACHANA. 
Width of regenerated margin in millimeters 
INDIVIDUAL | FIRST REGENERATION | SECOND REGENERATION 
} i] 
JING eto oO OO O ELEC AA BO rEAS ct Odors DOG A 1.6 1.8 
lic Ste date Ono CUBED AUD HOM ere Ape erran acre sion ol 2.0 
LO cre ict MICE Ce a CREE MRI RIN ey tones cor 8 1.4 
\Average = 1.2mm Average = 1.7mm. 
The general result in Cassiopea xamachana shows distinctly 
an increase in rate of regeneration with successive removal. ‘This 
is true not only when separate individuals are compared, but also 
when two segments within single individuals are used. ‘The influ- 
ence in this case seems therefore to be in part at least localized and 
not constitutional. ‘The greater difference shown between the first 
and second regenerations in separate individuals as compared with 
the differences between segments of single individuals indicates 
that the effect of successive removal is also partly constitutional. 
The agreement of all the individuals as far as the general result is 
concerned should be emphasized. However, the small number of 
