Zoology.-] NATURAL HISTORY OF VICTORIA. \Vohjzoa. 



I was at first inclined to refer this handsome species to M. Jlus- 

 troides (Hincks), but I think there is no doubt of their distinctness. 

 The zocecia are large, with a row of about 6 or 8 spines on each side. 

 These spines are very long, projecting forwards and inwards in a 

 very slightly curved manner, and, in some instances, nearly meeting 

 in the centre. In a few zocecia there are two shorter, smaller, 

 more erect spines at the upper end. The ocecium is small, semi- 

 globular and glistening. In the older there is a prominent, beak- 

 like projection from the lower margin ; in the younger the edge is 

 smooth. Occasionally there is an obscure elevation running down 

 the centre, and in some there is a thickening below showing an 

 approximation to the transverse collar in M. inarmata. 



Explanation of Figure. 

 Plate 127. — Fig. 4, portion of specimen, magnified. 



Plate 127, Fig. 5. 



MEMBRANIPORA SERRATA (McG.). 



Description. — Zocecia elongated, quadrate, or wider about the middle, or 

 pointed below; area occupying- the whole front, except occasionally the lower angles; 

 margin plain, w r ith a few acicular spines, or with numerous, serrated, horizontal 

 denticles. Avicularium on a separate area at the base of a zocecium; mandible very 

 long. Ocecium projecting into the base of the cell above, crossed by a band in front. 



References. — M. serrata, P. MacGillivray, Trans. Roy. Soc. Vict., 1881 ; 

 M. acifera, P. MacGillivray, Trans. Roy. Soc. Vict., 1881. 



Port Phillip Heads. 



This species can always be distinguished by the elongated, 

 quadrate zocecia, the position of the avicularium with its long- 

 mandible, and the rounded ocecium projecting into the base of the 

 zocecium above with its transverse collar formed by the cell-margin. 

 In some cases the cells are entirely unarmed ; in others there are 

 one, two, or more uncinate spines ; while, in most, the margins are 

 thickly fringed with short, broad-ended, serrated denticles directed 

 horizontally inwards. In many specimens the uncinate spines 

 alone occur, and in others there are only the serrated denticles, 



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