FORM-REGULATIONS IN CERIANTHUS. 



277 



A horizontal reading of the table gives the measurements for 

 each piece at each date and the last vertical column headed 

 " figure " gives the number of the text figure representing the 

 piece at the stage indicated by the horizontal division. 



It is readily seen from the table and figures that the length of 

 each piece gradually increases while its transverse diameter gradu- 

 ally decreases during the course of the experiment. The length 

 of the tentacles increases during the whole period. There are 

 several irregularities in the table which are undoubtedly due to 

 the great changes in form in individual specimens : for example, 

 piece A is shorter on November 6 than on October 29. This dif- 

 ference is merely temporary and due to the fact that the piece is 

 not as fully extended at the second measurement as at the first. 

 But the general result is sufficiently clear from both table and 

 figures. The extremely small size of the specimens on the day 



