Zoology.] NATUEAL HISTORY OF VICTORIA. \Tolyzoa. 



calcareous matter. This frequently accumulates largely round 

 the suboral avicularium, in an agglomeration above the mouth, and 

 in rounded elevations along the sides of the cells. In those cells 

 there are usually several round perforations on the outer edges of 

 the lateral nodules. The cells are also separated by distinct raised 

 lines. In some specimens a certain number of cells, frequently 

 grouped in close proximity, are very much larger. These large 

 cells differ also in having the mouth much wider and shallower, 

 and in the stellate pores not being confined to a small group, but 

 being more numerous and scattered over the whole of the central 

 part of the cell. They are frequently covered with rounded 

 calcareous masses along, but separated from, the edges, similar 

 masses being heaped up about the avicularium, which is sometimes 

 completely obscured by them, and also above the mouth. It is 

 difficult to say what these cells are, unless they are connected with 

 the ovicells. Besides the suboral, vertical avicularia, there are, in 

 some specimens, a few others very large and taking the place of 

 cells, as happens in E. platalea. The mandible is large and 

 triangular. They are mostly situated among the calcareous cells, 

 and their basis assumes the same appearance. 



E. mucronata may be always distinguished by the vertical 

 suboral avicularium and the central group of stellate pores. 



Explanation of Figures. 



Plate 48. — Fig. 6, the specimen described as Lepralia mucronata, natural size. Fig. 6a f 

 a portion of the same, magnified. Fig. 6b, a few cells, more highly magnified, showing the 

 simplest form Fig. 6c, cells from the same specimen, showing the perforated margin. 



Fig. 7, another specimen, natural size. Fig. la, a portion, magnified (the same extent as 6/* 

 and fie), showing a large solitary avicularium ; the cells are unusually large, and the upper one 

 approaches the characters of the very large ones. Fig. lb, small group, to show two of the very 

 large cells ; in these there is a large deposit of calcareous matter obscuring the suboral avicu- 

 larium ; the wide mouth and scattered pores are shown ; the smaller cells show the accumulation 

 of calcareous matter about the avicularium, which in the lowest is completely covered over. 

 Fig. 7c, cells from another large specimen ; in many cells of this it was difficult to make out 

 with certainty the stellate pores, owing seemingly to the presence of epidermis, but in a 

 considerable number they were quite apparent as figured ; throughout, the calcareous matter 

 was mostly accumulated on the avicularia and above the mouth. Fig. Id, a separate avicularium 

 from the same specimen, showing an increased deposit of calcareous matter. 



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