196 



HYDROIDS FROM NEW SOUTH WALES.* 



By E. a. Briggs, B.Sc, Zoologist, Australian Museum, 



Sydney. 



( C oinmuiiicated by A. R. McCidloch.) 



(Plates xxx.-xxxi., and Text-fig. 1.) 



i. Introduction. 



In 1911 Dr. Ritchie described, under the name of Sertularella 

 longitheca Bale, var. robusta, several hydroid specimens obtained 

 by the " Thetis" Trawling Expedition off the coast of New South 

 Wales. He had only sterile specimens for examination, but 

 several additional colonies bearing gonangia occur among some 

 Polyzoa, which were dredged by the same Expedition in New- 

 castle Bight, N.S.W., at a depth of 26-40 fathoms. In view of 

 the totally distinct gonangia, these specimens cannot be regarded 

 as belonging to a variety of Sertularella longitheca. The char- 

 acters are so distinct from those recorded, that it is necessary to 

 raise Ritchie's variety to specific rank. The name robusta is 

 preoccupied in the genus, and, therefore, I substitute Sertidarella 

 ritchiei. 



The second species here under discussion is represented in the 

 Australian Museum collection by some fine colonies from Marou- 

 bra Bay, near Sydney, N.S.W. 



ii. Descriptio7i of the Species. 



Order Calyptoblastea. 



Family SERTULARID^. 



Genus Sertularella Gray. 



Sertularella ritchiei, nom.nov. 



(Plate XXX., tigs. 1-2; Plate xxxi., fig.2; and Text-fig.].) 



Sertularella longitheca Bale, var. robusta Ritchie, Mem. Austr. 



Mus., iv., 16, 1911, p.841, PI. Ixxxviii., fig.8. 



* Contributions from the Australian Museum. 



