Zoology.'] NATURAL HISTORY OF VICTORIA. [Polyzoa. 



Description. — Zoaiium encrusting-. Zooecia arranged in single, bifurcating 

 series, pj-riform, with smooth surface ; aperture oval, occupying more than half the 

 front of the zooecium and with a slightly thickened margin, covered with a thin 

 membrane; two thin spines above at the upper extremity of the zooecium and two, 

 or usually three, short, sharp spines on each side of the aperture ; a long, flexible 

 spine immediately below the lower edge of the aperture. Ooecia situated above a 

 zooecium at the bifurcation of a branch, oval, the front surface covered by a series 

 of slender, converging ribs connected by a thin membrane and bounded by a narrow 

 calcareous line, beyond which is a smooth part. 



Reference. — Membranipoi-a aniplectens, Hincks, Ann. and Mag. Nat. Hist, 

 Aug., 1881. 



Port Phillip Heads, Mr. J. Bracebridge Wilson. 



I have only seen one not very good specimen on a piece of alga, 

 covered also with Schizoporella liualina. It is allied to E. joilosa-, 

 but is veiy much smaller. The ooecium is very peculiar. The 

 front wall is covered by a series of slender, white ribs converging 

 to a short line in the lower part. The ribs are bounded externally 

 by a narrow calcareous rim and are connected by a thin membrane 

 which is frequently slightly deficient at the margin. Beyond the 

 ribbed part is a narrow smooth portion. 



EXPLASATIOX OF FlGUKES. 



Plate IS". — Fig. 14, small portion of a, specimen. The zooecium of the commencing 

 branch at one side of the bifurcation below the ouecium is deficient. Fig. 14a, another portion 

 of tlie same specimen, showing three zooecia and an oa>cium, more highly magnified to show the 

 structure of the latter. 



Mr. MacGrillivray has contributed the specimens and descriptions 

 for this plate. 



Frederick McCoy. 



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