Zoology.-] NATURAL HISTORY OF VICTORIA. ^Polyzoa. 



In other specimens, liowever, it is much shallower and scarcely 

 distinguishable. The separating margins at their junctions with 

 the sides of the mouth occasionally rise to form an acute angle 

 projecting forwards.* 



Explanation of FionRE. 

 Plate 186. — Fig. i, portion of specimen, magnified. 



Plate 186, Fig. 5. 

 SCHIZOPORELLA BITURRITA (Hincks). 



Description. — Zoarium thick, encrusting" alg-ae. Zooecia confused, indistinct, 

 laro-e, oblong-; surface granular and perforated; mouth very large, with a deep, 

 wide, rather pointed sinus in the lower lip. A large triangular avicularium on the 

 inner side of a thick calcareous process on either side of the mouth. Ooecia large, 

 conical, surmounted by a thick, prominent umbo ; surface strongly granular and 

 perforated. 



Reference. — Hincks, Ann. and Mag. Nat. Hist., Oct., 1884. 



Port Phillip Heads. 



This very peculiar and striking species is readily distinguished. 

 It forms thick, calcareous layers, usually surrounding the stems of 

 small dark algfe. The zooecia are very indistinct, little prominent 

 except unmediately below the mouth. The surface is covered with 

 granulations and pores. The mouth is very large aud wide, with 

 a broad sinus in the lower lip. On each side of the mouth is a 

 stout, calcareous process, on the inner aspect of which is a large, 

 triangular avicularium with the mandible pointed upwards. The 

 upper part of this process is mamilliform and nearly smooth, the 

 lower part granular. The ooecia are very large, mamilliform, 

 sui'mounted by a nearly smooth, blunt umbo ; the remainder 

 covered with large granulations aud round jjores. These granu- 

 lations and pores are arranged in more or less radiating and 

 concentric series. 



Explanation of Figukes. 



Plate 186. — Fig. 5, specimen, natural .size. Fig. 5a, two zooecia and ooecia, magnified. 

 Fig. fib, ooecium and oral avicularium seen in profile. 



"Since the above was printed I have received specimens precisely agreeing with Hincks' figure and description, 

 and differing a good deal in tlie moutli from those previously examined by me. I will give a figure, with description, 

 in another plate. It may be doubted whether the present shoxild not be considered a distinct species. 



Vol. II.— Dbcade XIX.-2!/.' [ 313 ] 



