294 RECORDS OF THE AUSTRALIAN MUSEUM. 



Tlie liydrotliecte lie towards the distal ends of tlie intei'iiodes 

 and ai-e reniai-kable for tlieir lat-ge size and for tlie leni^tli of 

 tlie free portion. Tliey are distant, tubular, smooth and curved 

 outwards. The margin of tlie hydrotheca is divided into three 

 teeth, one adcHiiline, central and y)rojeetiiig', the others form- 

 ing an abcauline lateral pair. The teeth are separated by 

 deep embayments. The cavity of the hj'drotheca is only 

 partially cut off from that of the stem by the free end of the 

 adcauline wall, which bends sharply towards the interior of 

 the hydrotheca, forming a ledge at its base. There is a 

 tendency to regeneration of the hydrothecas, many of the mar- 

 gins being repeated twice or thrice. The colour of the colony 

 is light fawn. 



G 0)10801)1 e. — Unknown. 

 Ih'))ie))!^io)i>i : — 



Stem internode, length ... ... ... 1'04-1'16 mm. 



Stem internode, diameter ... ... 0"4!0-0"48 mm. 



Branch intei'iiode, length ... ... 0"73-0'87 mm. 



Branch internode, diameter ... ... 035-0"38 mm. 



Hydrotheca, length adnate ... ... 0"64-0"70 mm. 



Hydrotheca, length free ... ... ... 0"70-0"76 mm. 



Hydrotheca, diameter at mouth ... ... 0'50-0"53 mm. 



The present form has only three teeth, and belongs to the 

 Johnstoni — group of Hartlaub. 



Tupe Sj>ci')ii)i')i. — In the Australian Museum, Sydne}'. 



Genus Thuiakia, FlriiiiiKj. 



Thuiaria SINUOSA, Jlidr. 



(Plate .XXV.. fig. 1.) 



Thiiliiriii !<)in(ii.<i(, Bale, Proc. liinn. Soc. N. S. Wales, (2), iii., 

 l88cS, p. 772, pi. xviii., figs. 9, 10. hi, Ritchie, I\lein. 

 Austr. Mus., iv., 16, 1911, p. S44, pi. l.v.xxv., tig. k 



Several specimens referable in this species ai'e attachoil to 

 Polyzoon ci'usts by a series of tine stolonal tubes. The 

 colonies attain a height of iHo cm., and have a diameter of 

 3 mm. at the base. The stem is straight and polysi]dionic, 



