808 ME. J. RITCHIE OX HTDROIDS [May 24, 



cylindrical neck, the base of whicli is attached to the hydrotheca 

 at the chitinous projections already described. Distally this 

 swells out into a very definite bulb, which is surmounted by a 

 circle of from 18 to 20 tentacles. At the bases of the tentacles a 

 ring of very large bean-shaped nematocysts, 30 /* long hj 6 f/. 

 broad, surrounds the' hydranth. Similar cells occur in the 

 coenosarc of hydrocaulus and stolon. 



GososoME. — This does not appear to have been described. A 

 gonangium arises from the side of the hydrocaulus, about half-way 

 between the hydrotheca and the stolon. The female gonangiun* 

 is borne on a short stalk, and is roughly calceolate in shape, 

 resembling the female gonangium of H. beanii, except that here 

 the tubular orifice of the upper surface does not occur. All the 

 gonangia I have examined contain ova to the number of about 

 six. The male gonangium, therefore, remains unknown. 

 Dimensions : — 



Stolon, diameter 0'06-0'07 mm. 



Hydrocaulus, length 0-18-0-28 mm. 



Hydrotheca, depth 0-024-0-027 mm. 



„ diameter at margin O'08-OIO mm. 



Gonangium, length 0'42-0'50 mm. 



„ greatest diameter O'l 7-0-21 mm. 



Hydranth, length extended 1 '05 mm. 



„ • ,, contracted 0-78 mm. 



Locality. Epizoic on a polyzoon associated with Corydendrium 

 sessile, from St. 35, between Warden Island, Howe Island, and 

 Lyall Island, 15 to 20 fathoms, rock and sand. 



Hitherto recorded only from Amboyna, in the Moluccas 

 (Pictet, 1893, p. 22), this record adds the species to the fauna of 

 Indian seas. 



Halecium TEXELmsi Hincks (?), 1861. 



The trophosomes are lax in habit, and in all other respects 

 agree with Hincks's species ; but, in the absence of the gonosome, 

 confident identification is impossible, especially since the likeness 

 between the trophosomes of young examples of the Austi-alian 

 H. parvidum Bale and ff. tenelhim appears to be almost perfect 

 (see Markt.-Turner., 1890, p. 218). 

 Dimensions : — 



Stem, diameter 0-045 mm. 



Hydrotheca, depth 0-024-0-030 mm. 



„ diameter at margin 0-099-0-108 mm. 



The dimensions of the Mergui specimens are considerablv 

 smaller than those of British examples. 



Localities. Epizoic on Thyroscj/phvs vitiensis from Stations 15 

 and 16, Ravenshaw Island, Sir John Malcolm Island, and Alligator 

 Rock, 5 to 18 fathoms, rock and sand, or rock and mud. 



Recorded with some doubt from Eastern Australia bv Bale 

 (1884, p. 65) and Lendenfeld (1885, p. 405), this widely dis- 

 [lOJ 



