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



and thick, spirally annulated, especially at the commencement, but becoming smooth 

 upwards. 



Eeference. — Busk, Brit. Mus. Cat. Mar. Polyzoa, pt. i., p. 24, pi. xxviii., 

 figs. 4, 5. 



Port Phillip Heads ; Portland, Mr. Maplestone. 



Forms tufts about three-quarters of an inch high. It is readily 

 distinguished by the width of the branches, the large uncovered 

 aperture, and the anterior avicularium, which is situated on an 

 elevation directed upwards and forwards, the mandible opening 

 transversely upwards. The only species with which it can be 

 confounded is S. ferox (Busk), in which the mandible of the 

 anterior avicularium is very much larger. 



Explanation of Figures. 

 Plate 126. — Fig. 3, specimen, natural size. Fig. 3a, portion magnified, to show the 

 anterior surface. Fig. 3b, dorsal view of the same. 



Plate 126, Figs. 4-5. 



SCRUPOCELLARIA OBTECTA (Haswell). 



Description. — Zocecia 4-9 in an internode, broad ; aperture large, nearly 

 elliptical, with a very slightly thickened margin ; a large scutum* of the same shape, 

 and covering almost the whole aperture, with two groups of digitiform markings ; a 

 single stout spine at the upper and outer part. Lateral avicularian processes small ; 

 an anterior avicularium, of rather small size, below the aperture on a rigid elevation. 

 Vibracular setse short and smooth. A single vibracular cell at a bifurcation. 

 Ocecium globular, perforated by round foramina. Radical tubes smooth. 



Reference. — Hincks, Ann. and Mag. Nat. Hist., March 1883. 



Port Phillip Heads ; Mr. J. Bracebridge Wilson. 



This seems to be a rare species, as I have not found it among 

 my own dredgings. It is readily distinguished by its large, size, 

 and the very large scutum, which is marked by two groups of 

 conspicuous digitiform channels between its layers. Hincks 

 describes a spine also at the upper and inner angle, which does not 

 exist in the specimen examined by. me. He also, states that the 

 radical fibres are hooked. 



Explanation of Figures. 

 Plate 126. — Fig. 4, specimen, natural size. Fig. 4a, anterior view of portion of same, 

 magnified. Fig. 46, dorsal view. Fig. 5, zooecia and ooecia from another specimen, which is 

 much worn, except the ooecia, which are clear and distinct. This shows also an extraordinarily 

 developed avicularium. 



* This process, is in earlier descriptions, called the operculum, a term now generally restricted to the oral flap. 

 Smitt named it the fornix, and has been followed in the Challenger Tolyzoa by Busk, who, however, suggested the 

 present appellation, which has been adopted by Hincks, and is used here as being the most appropriate. 



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