OT Little Knoiun, Polyzoa. 35- 



C. plagiostoma and intermedia, but is readily distinguished 

 by its straight mouth, the shallowness of the fenestrge, the 

 shape and structure of the avicularian process, and the 

 markings on the back of the zooecia. 



Catenicella venusta, n. sp. PL I., fig. 1. 



Zoarium small ; branches slender, crystalline. ZocBcia 

 elongated, very narrow, with usually a sharp, barren process 

 on one side, and a thicker, aviculiferous one on the other ; 

 mouth subcircular, a narrow, sublateral vitta extending 

 about two-thirds of the length of the cell ; surface in front 

 slightly papillose. Ooecia elongated upwards, adnate on the 

 cell above, with a vertical thickened-line (showing the closure 

 of a fissure), margin with a thickened rim, inside which is 

 usually a series of white-bordered puncta. 



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



This lovely species is totally distinct from any pre- 

 viously described. The zooecia are remarkably slender. 

 The avicularian processes are directed upwards and 

 forwards ; one is usually sharply pointed and without 

 avicularium, while the other is thicker, and is surmounted 

 by a minute avicularium. The ooecium is very peculiar. 

 It is adnate to the zooecium above. It has a thickened 

 margin, within which there is usually a row of white- 

 bordered puncta; down the centre is a narrow band, 

 slightly clavate above, marking the site of an original 

 fissure, the lower part of which is still occasionally not quita 

 filled in. 



Family Escharid^. 

 Mucronella avicularis, n. sp. PI. I., fig. 3. 



Zoarium encrusting. Zooecia irregular, decumbent, im- 

 mersed, or oblique ; mouth with a quadrate denticle or 

 process on the lower lip ; surface obscurely granular. 

 Numerous large, broadly spatulate avicularia on large cal- 

 careous elevations irregularly scattered over the zoarium. 

 Ooecia subglobular, elevated. 



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



In this peculiar species the zooecia are irregularly 

 arranged, being sometimes nearly horizontal, and at others 

 more vertical, very much as in Cellepora. The most 



d2 



