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



a broad, thickened band at the margin, and with several glistening- lines radiating 

 on the summit. 



Reference. — Hincks, Ann. and Mag. Nat. Hist., Nov. 1880. 



Port Phillip Heads ; Portland, Mr. Maplestone. 



At once distinguished from M. pyrida and the other spinous 

 species by the large, pod-like, articulated oral spines. Of these 

 there are usually 4, but sometimes only 2. The marginal spines 

 arise from bulbous origins closer to the margin than in M. pyrula, 

 and bend over the area, meeting in the centre and frequently 

 overlapping. The zoarium occasionally creeps over Bicellaria and 

 other Polyzoa in a single, linear series. . 



Explanation op Figure. 

 Plate 127. — Fig. 2, group of zooecia, showing an ocecium, magnified. 



Plate 127, Fig. 3. 



MEMBRANIPORA INABMATA (Hincks). 



Description. — Zooecia large, distinct, usually oval, and rounded above and 

 below j area occupying the whole of the front of the cell ; a small, nearly erect spine 

 on each side above, and a series (about 5 or 7) of narrow, incurved spines on each 

 side. Ocecium projecting into the base of the zocecium above, crossed at its base by 

 a band formed by the cell-margin. 



Reference. — Hincks, Ann. and Mag. Nat. Hist., July 1881. 



Port Phillip Heads, dredged by Mr. J. B. Wilson and myself. 



The marginal spines are much more slender and have wider 

 intervals between them than in M. pyrula and corbula. The 

 ocecium projects into the base of the cell above, and has a 

 thickened collar at the base formed by the cell-margin, an arrange- 

 ment which also occurs in M. serrata. 



Explanation op Figures. 

 Plate 127. — Fig. 3, group of zooecia, showing ocecia. Fig. 3a, single zocecium, with ocecium. 



Plate 127, Fig. 4. 



MEMBRANIPORA PECTINATA (McG.). 



Description. — Zooecia large, distinct, oval; 6-8 long, stout spines on each 

 side, sloping forwards and inwards, and nearly meeting in the middle. Ocecia small, 

 smooth, with the edge of the orifice straight, or with a short, sharp beak. 



Port Phillip Heads. 



C 104 ] 



