185 HYDR01DA. HALE. 



In all these points the specimens coincide with Billard's 

 figures. The absence from those figures of the median lateral 

 lobes of the hydrotheca-niargin is immaterial, as Billard mentions 

 that the specimens were not in a condition to enable him to make 

 out clearly the exact form of that part. 



The little circular orifices, of which both mesial and lateral 

 sarcotheca? possess two, are still more profusely developed in 

 those of the hydrocaulus, the two in front usually having from 

 three to five, while the one behind the axil commonly has six or 

 seven. 



The lateral sarcothecae are very large, and in side view they 

 mostly overlap the base of the next hydrotheca, often even to a 

 greater extent than shown in the figure. 



Loc. Great Australian Bight, 80-120 fathoms. 



HALICOKNARIA VKG^;, Jaderliolm. 

 (Plate xxxvi., figs. 4-5.) 



Halicornaria Vegce, Jaderholm, Aussereuropaische Hydroiden 

 im Schwedischen Reichsmuseum, 1903, p. 301, pi. 15, 

 fig. 1-4. 



Hydrophyton about eight inches in height, stem slightly 

 geniculate, fascicled below, dividing into three at each genicula- 

 tion ; side branches three or four inches long, divergent on 

 alternate sides, monosiphonic, bearing only sarcothecaa on the 

 proximal portions, nodes oblique. Hydrocladia short, alternate, 

 one on an internode. 



Hydrothecas very large and stout, almost parallel with the 

 internode, campanulate in front view and narrow except towards 

 the aperture, where they are expanded ; in side view much 

 stouter, and narrowed towards the aperture ; smooth, with no 

 intrathecal ridge nor fold ; a small process projecting from the 

 lower edge of the hydropore, with two or three minute denticles ; 

 border circular, with a distinct anterior tooth, otherwise entire, 

 smooth or faintly undulated, back free; a slight longitudinal 

 fold running up the front. No septal ridges. 



Mesial sarcotheca tubular, small, projecting at a wider angle 

 than the hydrotheca, to the basal part of which it is adnate ; 

 free portion short, contracted, with terminal and inferior aper- 

 tures, which are generally distinct though closely approximate. 

 Lateral sarcothecae small, ovate, closely adnate, apertures as in 

 the mesial. Cauliuesarcothecge similar to the laterals, two at the 

 base of each hydrocladium in front and one behind the axil. 



Gonosonie ? 



