Zoology.-] NATURAL HISTORY OF VICTORIA. [Pohjzoa. 



a narrow, entirely lateral vitta extending- the whole length of the zooecium ; lateral 

 processes small, usually with a sharp angle above projecting outwards and forwards; 

 a minute avicularium opening outwards on the outer edge. Ocecium cemented to 

 the front of the zooecium above, with a quadrate smooth area. 



Reference. — P. H. MacGillivray, Trans. Roy. Soc. Vict, Nov. 1884. 



Port Phillip Heads, Mr. J. B. Wilson. 



In this small species the zocecia are exceedingly slender. The 

 ocecium, which is cemented to the cell above, as in C. elegans, 

 Buskii, fusca, and some others, has on the front a smooth, quadrate 

 area, totally different from the markings of any other species. 



Explanation op Figuees. 



Plate 146. — Fig. 3, anterior surface of portion of a branch, magnified. Fig. 3a, posterior 

 view of same. 



Plate 146, Fig. 4. 



CATENICELLA VENUSTA (McG.). 



Description. — Zoarium small ; branches very slender, crystalline. Zocecia 

 elongated, very narrow, with usually a sharp, barren process on one side and a 

 thick aviculiferous one on the other; mouth sub-circular; a narrow, sub-lateral 

 vitta extending about two-thirds of the length of the zooecium ; surface in front 

 slightly papillose. Ocecia elongated upwards, adnate to the cell above, with a 

 vertical thickened line (indicating the closure of a fissure), margin with a thickened 

 rim, inside which is usually a series of white-bordered puncta. 



Reference. — P. H. MacGillivray, Trans. Roy. Soc. Vict., March 1886. 



Port Phillip Heads, Mr. J. B. Wilson. 



In this lovely species, the zocecia are remarkably slender. The 

 avicularian processes are directed upwards and forwards ; one is 

 .isually sharply pointed and without avicularium, while the other 

 is thicker, and is surmounted by a minute avicularium. 



i 



Explanation of Figures. 



Plate 146.— Fig 4, anterior view of portion of a branch, magnified ; an ocecium shows the 

 vertical fissure only partially closed. Fig. 4a, two zocecia and mature ocecium. Fig. 46, posterior 

 view of portion of same branch. 



C 175 ] 



