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



Plate 48, Fig. 8. 

 CALESCHAEA DENTICULATA (P. MacGil.), 



[Genus CALESCHARA (P. MacGil.)- (Sub-kingd. Mollusca. Class Polyzoa. Order 

 Infundibulata. Sub-Ord. Cheilostomata. Fam. Escharidae.) 



Gen. Char. — Polyzoar y expanded, foliaceous, erect, not perforated. Cells horizontal, 

 opening on both surfaces, separated by raised lines, and depressed in the centre. Front cal- 

 careous, except a small part anteriorly, which is membranous.] 



Description. — Polyzoary small, foliaceous, convoluted. The cells are wide 

 and rounded above, contracted below, separated by raised, smooth, or minutely 

 crenulated margins. The front is depressed in the centre, and is covered by a mem- 

 brane, through which the deeper calcareous layer may be obscurely seen. When 

 this is removed, as it frequently is by attrition or decay, the edges are seen to be 

 bevelled inwards, and about a sixth or a fourth part of the front within the bevelled 

 portion is entirely membranous ; the arched mouth is situated at the upper part of 

 this. The rest of the front is calcareous, except a large slit on each side. At the 

 junction of the membranous anterior part there is an increased deposit of calcareous 

 matter, forming a thickened convex band, the anterior edge of which is smooth or 

 finely denticulate, or tubercular. The outer edge of the slit-like opening corresponds 

 to the inner bevelled margin. It is granular, like the bevelled part. The inner edge 

 is produced into a series of minute, pointed, horizontal denticles. The lamina 

 between the slits slopes backwards on each side, and is occupied by numerous pores 

 or small tubercles. In some cells there is a small, rounded prominence in the angle 

 above the mouth which might be mistaken for a minute ovicell. The ovicelligerous 

 cell is very large, and the ovicell is wide, little projecting, and incorporated with the 

 cell above, which also is of unusual size. 



Reference. — Eschara denticulata, P. H. MacGillivray, Trans. Roy. Soc. Vict. ? 

 1869. 



Queenscliff ; Schnapper Point ; Warrnambool, Mr. Watts. 



This differs from the old genus Eschara in the anterior part 

 of the cell being membranous, and the front depressed in the 

 centre. The membranous part varies considerably in extent, and 

 in some cells the mouth seems to occupy the whole aperture, the 

 thickened calcareous band resembling a lower lip, while in others 

 the operculum occupies only a small portion. All the specimens I 

 have seen have been cast on the beach and been dried, so that it is 

 impossible to say whether the anterior membranous layer is closely 

 adherent to the calcareous lamina. 



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