Vol. V. October, ipoj. No. 5 



BIOLOGICAL BULLETIN. 



FORM REGULATION IN CERIANTHUS. 



I. THE TYPICAL COURSE OF REGENERATION. 

 c. M. CHILD. 



INTRODUCTION. 



During the year 1902-1903 it was my privilege to spend sev- 

 eral months at the Zoological Station in Naples, as holder of 

 the Smithsonian table. I take this opportunity to express my 

 great indebtedness both to the Smithsonian Institution for the 

 grant and to Professor Dohrn and all other members of the staff 

 of the Zoological Station. A part of my time at Naples was 

 devoted to the study of regeneration and other regulative proc- 

 esses in the Cerianthidae, and an account of these observations 

 and experiments is begun in the present paper. 



So far as I am aware the only work upon regulation in Cerian- 

 tlnis is that of Loeb. 1 A review of this work is unnecessary at 

 this time since the various points will be discussed in connection 

 with my own observations as occasion arises. 



My observations and experiments upon the Cerianthidae fall 

 into a number of groups, and, since they are somewhat extended, 

 the account of the subject will be divided in a corresponding 

 manner. In the present paper the usual "normal' course of 

 regeneration resulting in a perfect animal is described. Later 

 the problem of experimental control of regulation will be taken 

 up, then variation and abnormalties in regulation and the factors 

 concerned in their production. 



THE NORMAL ANIMAL. 



It is necessary to call attention to a number of the features of 

 the normal anatomy and habits before proceeding to the descrip- 

 tion of the regenerative phenomena. 



1 Loeb, J., " Untersucbungen zur Physiologischen Morphologic der Thiere," I., 

 Wurzburg, 1891. 



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