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



also varies very much, being of moderate size and smootli, or large 

 and granular or tubercular. The zooecia are usually smooth, but 

 may be covered with large granulations, and the margin has 

 frequently a row of perforations. The ocecia are at first prominent, 

 but become immersed with age. In the older ones the opening is 

 closed by a thick operculum, which may be smooth or faintly 

 granular or lined. When deeply immersed the operculum is 

 nearly vertical. 



I have several specimens on shell from shallow water which I 

 was at one time inclined to consider as a distinct species. It may 

 be called var. delicatula. All the zooecia are horizontal. The 

 uncinate and opposite oral processes unite or nearly so, and a 

 roimd elevation is formed on the base of the former. Two glassy 

 elevations first appear below the mouth followed by others over 

 the surface of the older zooecia. There are few or no avicularia. 

 The ooecia are prominent, smooth, or with a slight umbo, and the 

 opening is small and has no apparent operculum. 



Explanation of Figures. 



Plate 195. — Fig. 7, usual appearance of older colonies, showing confusion of cells and oral 

 and zocecial aricularia. Fig. 8, group of young cells from growing edge of another colony. 

 Fig. 9, marginiil zooecia from edge of specimen of var. drlicatula, showing primary mouth, 

 uncinate and oral processes, uncinate process with rostral elevation, and two elevations on front 

 of zocEcia. Fig. 10, single oral opening from another specimen. 



Plate 196, Figs. 11-14. 

 RHYNCHOPORA LONGIROSTRIS (Hincks). 



Description. — Zoarium adherent. Zooecia wlien young, large, ovate or pyri- 

 form, distinct, frequently separated by rows of pores, smooth at the extreme edg-es of 

 the colony but becoming slightly granular farther back; primary mouth transversely 

 elliptical, without sinus; when old indistinct, granular, mouth quadrate, an uncinate 

 process to one side of the lower lip with the sharp point directed nearly across to the 

 other side; below the uncinate process is a small avicularium with broadly triangular 

 mandible on an elevation, which also is frequently developed into a mucro. Numerous 

 large avicularia on the front of the zooecia with long, ligulate mandibles pointing 

 downwards. Ooecia immersed, smooth or slightly granular, with a calcareous 

 operculum. 



References. — Hincks, Ann. and Mag. Nat. Hist., Aug., 1881; Ji. profunda, 

 MacGillivray, Tr. Roy. Soc. Vict., Oct., 1881. 



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