257 



of which bears an onecium, but otherwise it does not seem to appear in bi-zooe- 

 cial internodes. The aviciilaiium has a somewhat ascending roof and a robust 

 beaked hook. It communicates on its basal side with an extremely small snpra- 

 scapular chamber with an oval o])ening, and forms a deep sinus together with 

 the trapeziform infra-scapular chamber, which has a truncated conical process 

 and a rounded frontal opening. When not developed as an avicularium the 

 scapular chamber appears as a generally long, compressed, conical, spine-like 

 process, which ascends obliquely and is directed basally and on which the supra- 

 scapular and the infra-scapular chambers are indicated by a perforation on each 

 of its two surfaces. The proximal part of this process, which corresponds to the 

 infra-scapular chamber, is however not infrequently conically projecting and 

 separated from the other part of the spine by a deep sinus. The pedal chamber 

 is of moderate breadth and its ojjening can only be seen when the zoa-cium is 

 regarded from the side. It reaches right up to the infra-scapular chamber and 

 its length is two-thirds of the zoacium. On the bi-zooecial internode there is a 

 small, oval boundary chamber (m. III). 



The ooecium. The gonozorecium is always a mother-zonecium, and the ooecium 

 is covered by a kenozoa'cium. The latter generally ends in a shorter or longer 

 conical spine, which must be regarded as an unpaired scapular chamber. More 

 rarely we find a small cavity with a membranous roof. The kenozoo'cium, the 

 frontal wall of which is sometimes whole, sometimes provided with a median 

 pore, has on either side a pedal chamber, which is placed on the basal surface 

 and is pi-ovided with 3 — (i iincalcificd rosette-j)lates, disposed in a single or a 

 double row. The proximal part of the operculum of the gonozooecium is covered 

 by a thin, erect under-lip, and on the abzooecial side we find a spine-like scap- 

 ular chamber opposite to the aperture, whereas the abzoa?cial scapular chamber 

 on the corresponding daughter-zod'cium is most often developed as an avicul- 

 arium. In the examined colony the mother-zoa'cium may be developed as a gono- 

 zoo'cium in up to three succeeding bi-zotiecial internodes. 



Form of colony. In this species uj) to four bi-zoa-cial internodes often succeed 

 each other, and rows of single zoa?cia only are never seen. 



Colonies from Port Phillip (Miss Jelly). 



Strophipora Mac Gillivray. 



A slernal area as well as an inner cryptocyst lamina are wanting in the zo(i'- 

 cia, and the whole of the frontal surface is covered by the two infra-scapular 

 chambers, which are separated by a narrow longitudinal ridge in the central 

 line of the frontal surface. A little proximally to the aperture we find a median 



17 



