Lord Howe Island Polyzoa. 389 



always more or less visible, and their presence, together with 

 the tubercular surface, showed that, notwithstanding all these 

 variations, they must be considered as belonging to the same 

 species. 



Schismopora cucullata, nov. sp.. (PI. XXTX., Figs. 7, 8). 

 Adult zooecia globular, subimmersed, irregularly arranged ; 

 surface granular. Thyrostome arched above, straight below, 

 with a rounded sinus in the lower margin ; large triangular 

 avicularia situated upon large globular bases scattered over the 

 zoarium. The marginal (young) zooecia are decumbent ; they 

 have four long thin spines on the distal margin. The thyrostomes 

 of some have a small mucro on the proximal margin, which 

 probably carries a small avicularium ; this disappears in the 

 adult form. Ooecia immersed with a hoodlike structure above, 

 the aperture of the same shape as that of the zooecia, but 

 smaller. The zooecia in the older portion of the zoarium are 

 very crowded and irregularly disposed ; the hoodlike structure 

 of the ooecia is very peculiar. 



Mucponella centpota, nov. sp. (PI. XXTX., Fig. 9). 



Zoarium encrusting. Zooecia elongated, but indistinct ; 

 covered with mamilliform tubercles, which in the median line 

 rise up so as to form a ridge. Peristome raised with a long 

 thick spinous projection on each side with two small spines on 

 the distal margin between them ; proximal margin very 

 irregTilarly serrate. 



I place this in Mucronella because it is something like M. 

 ellerii in appearance, but the form of the thp'ostome is not 

 visible in the specimen, so that its position is somewhat 

 doubtful. 



Cpisia howensis, nov. sp. (PI. XXIX., Figs. 10, 11). 



Zoat'ia branching ; from three to seven zooecia is an internode. 

 Cells minutely and sparsely punctured, elongated and produced, 

 with a tubular orifice. A long articulated and jointed spine on 

 one side of the zooecial tube. Ooecia ovoid, densely punctured, 

 orifice not visible. 



