UNIVERSITY OF CALIFORNIA PUBLICATIONS 



ZOOLOGY 



Vol. 1, No. 6, pp. 211-226. May 10, 1904 



REGENERATION AND NON-SEXUAL 

 REPRODUCTION IN SAGARTIA DA VISE 



BY 



BARRY BEAL TORREY and JANET RUTH MERY. 



This paper embodies a preliminary account of investigations, 

 as yet unfinished, the present results of which it lias seemed 

 desirable to publish without waiting for the completion of our 



w< >rk . 



I. NON-SEXUAL REPRODUCTION IX SAGARTIA 

 DAVISI. 



N. davisi reproduces non-sexually by longitudinal fission onlj . 

 though in some cases the fission resembles rather closely in some 

 respects the process of basal fragmentation, so common in 

 Metridium and. according to G. C. Davenport ('()•'!). probablj 

 occuiTing in 8. luciae, the eastern representative of 8. davisi. 

 Three types of fission are distinguishable in 8. davisi: 



1. Aboral-oral fission by constriction, accompanied by 

 rupture. 



.!. Aboral-oral fission by constriction alone. 



3. Fission proceeding from side to side, by rupture. 



McCrady ('58) observed aboral-oral fission in a South 

 Carolina cribrinid which he called Actinia cavernosa, but he did 

 not see tin' completion of the process. <i. C. Davenport has 

 recently (:(>(>, :03) observed similar phenomena in 8. luciae, 

 following the process to completion. In the descriptions of both 

 authors few details are mentioned, and no distinction is made 

 between fission bj constriction and lission by rupture. Carlgren 

 ('93) has recorded a case of aboral-oral fission in Protanthea 

 simplex; but. as Torrey ('98) indicated in commenting on a 



