84 



University Studies 



Vol. Ill OCTOBER, ipoj No. 4 



I. — Regeneration in- Hydroinedusae^ 



BY GEORGE THOMAS HARGITT 



I. Introduction 



Considerable work has been done on the regeneration and 

 grafting in the Hydrozoa by Loeb, Bickford, Driesch, Hargitt, 

 Peebles, IMorgan and others. The results of these experiments 

 have been, at times, somewhat antagonistic. The work among 

 the Tubularians has been largely limited to Tubularia crocca and 

 T. incseinhryanthcnuini, and the histological work has been 

 neither extensive nor conclusive. The work of which this paper 

 is a record was therefore undertaken to review certain experi- 

 ments and to throw some light on disputed or inconclusive state- 

 ments, as well as also to carry out careful histological studies 

 on the regenerated structures. The experimental work was done 

 during the summer of 1901 at the marine laboratory at Woods 

 Hole. The histological work was started the next winter at Syra- 

 cuse University, and completed in the spring of 1903 at the 

 University of Nebraska. 



To my father, Dr. C. W. Hargitt, I am greatly indebted for 

 supervision and helpful suggestions during the early part of the 

 work. 



^Studies from the Zoological Laboratory, The University of Nebraska, 

 under the direction of Henry B. Ward, No. 57. 



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