HYDROZOA FROM ONE HUNDRED FATHOMS, 

 SEVEN MILES EAST OF CAPE FJLI.Ali, TASMANIA. 



By E. A. BRKids, B.Sc, Zoologist 



(Plates xxv.-xxvi., and Fig. 1.) 



The small collection of Hydi'oids desciihed Iti <lie pi'eseiit 

 paper forms part of the marine invertebi'ate collections 

 obtained by Messrs. C. Hedle}' and W. L. May, seven miles 

 east of Cape Pillar, Tasmania, in December, 1907. The 

 specimens are of interest as being the fii'st samples of the 

 Hydroid fauna of Tasmania from one hundi-ed fathoms. 



The specimens were dredged " on a firm bottom of sand, 

 rolled pebbles, and a conglomerate of recent sliells."^ 



The collection is composed entirely of Calyptoblastic foi-ms, 

 and contains representatives of thii'teen species, one of which 

 is new. 



The male corbulii? of Aylaophe)iia fasmiunca have been 

 described for the first time, and an instance of sexnal 

 dimorphism lias been observed in the structure of the corbulae 

 of tliis species. 



The most striking of the records of geographical distribu- 

 tion are as follows : — 



Ferisljihuiiid exseyta (Johnson), previously reported by All- 

 man and Ritchie from Australian sea.s, was originally found in 

 the North Atlantic at Madeira; TJniinn'd siinio.iu, 3?i]e, was 

 previously recorded from Port Molle, Queensland, and Jervis 

 Bay, New South Wales ; and Tliyru^cyphas si iii [ilex, ori^umUy 

 described by Lamouroux " sur les Fuscus de 1' Australasie,"^ 

 has been recorded by Ritcliie in a recent paper from the Clyde 

 Sea Area and from Gough Island, South Atlantic. 



I He.lley and May— Rec. Austr. Mus.. vii., 2, 1908, p. 108. 

 ■-' Lamouroux— Hist. Polyp. Cor. Flex., 1816, p. 207. 



