122 A NEW FAMILY OF HYDROIDEA. 



placed the family in the group Porifera. Mr. Carter suhsequently had the opportunity 

 of examining both Dr. Gray's specimens and otliers of allied forms from New 

 Zealand and the Cape, and rightly referred them all to the Hydroidea, placing them 

 in the family Hydractiniida^. This classification was adopted by Dr. v. Lendenfeld, and 

 also, at first, by Mr. Bale in his valuable contribution to the literature of Australian 

 zoology — the "Catalogue of Australian Hydroid Zoophytes."* Subsequently, Mr. 

 Bale had the opportunity of examining spirit-preserved specimens with the hydranths 

 and soft parts present, and, finding that these differed very considerably from those 

 of the Hydractiniidae in the presence of irregularly distributed capitate tentacles, 

 &G., rightly separated them once more from the Hydractiniida?, and adopted the 

 name of CerateJladae for the family, f I was unaware of this short paper of Mr. 

 Bale's until my attention was kindly drawn to it by Mr. Whitelegge, of the 

 Australian Museum. 



Whilst Dehitella in its general form (in the dried specimen) is somewhat like 

 the specimen obtained by Mr. Wilson, there can be little doubt that the two are 

 markedly distinct, even so far as the skeleton goes. Dehitella has most clearly what 

 have well been called hydrophoresj, and agrees closely in this respect and in the 

 general formation of its skeleton with Ceratella ; in their soft parts we may 

 reasonably suppose that a corresponding agreement exists. Now the soft parts of 

 the Ceratella are known, § and they differ very strongly from those of the form with 

 which this paper deals, so that we are probably correct in assuming that a similar 

 difference exists between the latter and Dehitella. There is, on the other hand (as 

 will be shown subsequently), quite as marked a distinction between the new form 

 and any member of the family HydractiniidiB as exists between the former and the 

 Ceratellada3, so that it is necessary to create a new family for its reception. 



I have not so far, though numerous sections have been cut, been able to 

 detect any reproductive elements, and therefore the description is incomplete, but will 

 quite sufficiently serve to distinguish it from other forms. 



Family HydroceratinidcE. 



Hydrophyton, consisting of a mass of entwined hydrorhiza, with a skeleton in 

 the form of anastomosing chitinous tubes ; the surface is studded with tubular 

 hydrothecfe, into which the hydranths can be completely retracted. Hydranths 

 sessile and connected with more than one hjdrorhizal tube, claviform with a single 

 verticil of filiform tentacles. Defensive zooids present with a solid endodermal axis 

 and nematocysts borne at the distal end. 



* Catalogue of Australian Hyilroid Zoophytes. W. M. Bale, 1884. 



t Bale, Proo. Liiiii. Soc, N.S.W., Vol. III., pt. 2, p. 748 ; also Brazier, Proc. Linn. Soc, N.S.W., new series. Vol. I. 

 page 575 ; Whitelegge, loc. cit., p. 578. 



} Bale, Proc. Linn. Soc, N.S.W., 1888, p. 749. 

 § Bale, loc. cit. 



