HYDROID ZOOPHYTES. 13 



TUBULARIA RALPHI. 



(Plate II., fig. 12.) 

 Tubularia ralpUi, W. M. Bale, Cat. Austr. Hydroid Zoophytes Austr. Mus. (1884), p. 42. 



Localities. — W.Q., February 28th, 1902; -20 fms. Hut Point, October 18th 

 and November 13th, 1902. Flagon Point, January 17th, 1902 ; 10-20 fms. 



This species is represented in the collection by a group of dead perisarcal tubes 

 and a single hydranth which is not well preserved, as well as by a few immature 

 specimens. 



Hydrosome. — The height of the colony is from 60-120 mm. In the W.Q. 

 specimen, five long and slender hydrocauli arise from a contorted hydrorhizal plexus. 

 Each hydrocaulus is unbranched, and considerably narrower at the base than at the 

 distal extremity, where its diameter is about • 8 mm. The perisarc covering the 

 hydrocaulus is smooth and conspicuous, but becomes very thin and transparent at the 

 base of the hydranth. The hydranth is flask-shaped, and has a dense tuft of distal 

 tentacles and a circlet of about twenty or more proximal tentacles each about 

 5 mm. in length. 



Gonosome. — The blastostyles arise immediately above the proximal row of 

 tentacles. Owing to the condition of the specimen, their number could not be 

 accurately determined. 



The ripe gonophores (females only were observed) are somewhat pear-shaped, and 

 provided distally with four rudimentary tentacles. The walls of the umbrella are very 

 thin, but the sub-umbrella cavity is large, and usually contains more than one, but not 

 more than three actinulse. No trace of tentacles could be observed on these larvae. 



The blastostyles are very short, and the gonophores are borne upon them in dense 

 clusters, so that it is probable that in life they were not pendulous. The blastostyles 

 are about 2 mm. in length, and each ripe female gonophore about 1 mm. in length. 

 The male gonophores of another specimen were not mature. 



The only printed description (4 : p. 42) of the type of this species which was 

 found in shallow water in Hobson's Bay, Victoria, is so short that it is impossible to 

 be certain that our identification of these Antarctic Tubularias is correct, but, except 

 in the fact that our specimens are rather larger than the type in several measurements, 

 there is no good reason for separating them from it. 



Tubularia hodgsoni. 



(Plate II., fig. 13, and Plate IV., fig. 34.) 



Locality.—W.Q,., January 1st, 1902; No. 6 hole; 130 fms. No. 11 hole, 

 April 25th, 1903. 



Unfortunately, only two zooids of this remarkably interesting species were found. 



