Descriptions of New, or Little Known, Polyzoa. 115 



considerableboat-like elevations; some spatulate and smaller; 

 some on rounded cells, with broad mandibles, the upper edge 

 of the rostrum serrated. 



Port Phillip Heads. 



The most marked peculiarity of this species is the great 

 abundance and extraordinary forms of the avicularia. The 

 marginal cells are elongated and decumbent ; the very 

 youngest have the mouth straight and entire below, but in 

 almost all a process of the peristome is seen rising on each 

 side and meeting in the centre, leaving a round opening 

 (Fig. 4c), which in time becomes filled in. Below the mouth 

 a process rises on one side, extending upwards and curving 

 over to the opposite side, with a considerable avicularium on 

 its summit, the top of the process, where the mandible shuts 

 down, being serrated. In some marginal cells this process 

 is very large and directed upwards (4a), the avicularium 

 situated obliquely on the summit. In some (4c) it is much 

 smaller. The older cells vary much in shape, being usually 

 short and oblique, or nearly erect. The oral pore of the 

 peristome can frequently still be seen, and the peristome 

 is also in some cases produced above in a hooded manner 

 somewhat like a commencing ovicell. In one or two the 

 peristome is almost tubular, with a slit in the lower edge. 

 The aviculiferous process below the mouth is usually of 

 small size. Besides, the avicularium on this process, there 

 is a multitude of others scattered over the zoarium. Some 

 are small and spatulate, others of the same shape but of 

 enormous size and much raised, the point of the calcareous 

 eminence projecting over part of the neighbouring cells. 

 Others are broad and thick, almost globular, either separate 

 or taking the place of the suboral process, with broad man- 

 dibles, the upper receiving edge of the cell or rostrum being 

 serrated. Besides these, there are a few of great size, pro- 

 jecting above the surface of the zoarium, with very large 

 broad mandibles and the upper edge serrated (Fig. 4cZ). 

 The whole surface of the cells and avicularian cells is finely 

 granular. 



Cellepova mega-soma, M'G. Plate III., fig. 5. 



Zoarium encrusting. Cells ovoid, irregularly arranged, 

 frequently bulging below, and with an imperfect umbo. 

 Mouth arched above, about as high as wide, with a rather 

 sharp sinus in the lower lip. Scattered avicularia, frequently 



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