HYDROID FAUNA OF THE BERMUDAS. 251 



Sertularia cornicina was found on the ledges and on Sargassum at both 

 Agar's Island and Somerset Bridge, also on a gorgonian dredged in 32 

 fathoms on Challenger Bank. The latter specimens showed the for- 

 mation of unusually long stolons from the tip of the colony back to the 

 hydrorhiza. No sign of the often epizoic Hebella calcarata was seen. 



Sertularia aestuaria Stechow. 



Sertularia humilis, Congdon, 1907, p. 479, figs. 29-32. 

 Sertularia aestuaria, Stechow, 1919, p. 157. 



This very common sertularian frequently formed thick mats over 

 the ledges at about the low-tide mark in practically all the locali- 

 ties visited. The specific name humilis was used in 1879 by Arm- 

 strong (Jour. As. Soc. Bengal, vol. 48, p. 101, tab. 9) for Desmoscyphus 

 humilis of the Indian Ocean, and Stechow has suggested for Congdon's 

 S. humilis the name 8. aestuaria, descriptive of its habitat at tide-level. 



Sertularia stookeyi Nutting. 



Nutting, 1904, p. 59, pi. 5, figs. 6, 7. 

 Fraser, 1912, p. 375, fig. 39. 



A large number of colonies, with gonangia, were taken on floating 

 Sargassum both off the north shore and in Hamilton Harbor. In 

 many cases there was profuse growth of stolons from the extremities. 



Sertularia versluysi Nutting. 



Desmoscyphus gracilis, Allman, 1888, p. 71. 

 Desmoscyphus inflatus, Versluys, 1899, p. 42. 

 Sertularia versluysi, Nutting, 1904, p. 53, pi. 1, figs. 4-9. 

 Sertularia versluysi, Congdon, 1907, p. 481. 

 Sertularia versluysi, Fraser, 1912, p. 375, fig. 40. 



Genus Thyroscyphus. 



Thyroscyphus intermedius Congdon. 

 Congdon, 1907, p. 482, figs. 33-36. 



