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

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

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

 scapular chamber with an oval opening, 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 opening can only be seen when the zocecium is 

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

 its length is two-thirds of the zocecium. On the bi-zocecial internode there is a 

 small, oval boundary chamber (m. III). 



The ooecium. The gonozooecium is always a mother-zocecium, and the ooecium 

 is covered by a kenozooecium. 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 kenozooecium, 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 provided with 3—6 uncalcified rosette-plates, 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 abzooecial scapular chamber 

 on the corresponding daughter-zooecium is most often developed as an avicul- 

 arium. In the examined colony the mother-zocecium may be developed as a gono- 

 zooecium in up to three succeeding bi-zooecial internodes. 



Form of colony. In this species up to four bi-zocecial internodes often succeed 

 each other, and rows of single zooecia only are never seen. 



Colonies from Port Phillip (Miss Jelly). 



Strophipora Mac Gillivray. 

 A sternal area as well as an inner cryptocyst lamina are wanting in the zooe- 

 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 



