A MONOGRAPH OF THE TEIITIA.RT POLTZOA OF VICTORIA. 11 



W.P. LiviuEf. Mediterranean. 



This agrees with Busk's description and figure, hut I donht whether it is the 

 Cellepora Mirpocrepis of Hagenow. The cliaracter of tlio liroad plate on the lower 

 edge of the aperture, which is similar to that of the last species, makes it prohahle 

 that when hetter specimens are availahle, it will be found that both species should 

 be referred to SterjauoporoUa or a new genus of which (S*. patitJa would be the type. 



Amphiblestrum, Gray. ,,,, 



Zoarium encrusting or erect. Area occupying the whole front or with part of ('^' ii 

 the zoa?cium produced below ; area partly filled in by a niembrano-calcai'eous or ^^<t^^^}^'^^ 

 calcareous lamina. 



1. A. simplex, n.sp. PL V., fig. 20. 



Zoarium cylindrical. Zoa?cia elongated, quadrate, alternate in longitudinal 

 series, sejjarated by distinct raised margins, the transverse portions of which are 

 prominent ; aperture; occupying rather more than half tbe area, elliptical, extending 

 quite to the margins above, edges smooth and slightly thickened, lamina smooth or 

 faintly granular. No avicularia. 



S.P. ; M.C. 



2. A. hursarium, McG. PI. Y., fig. 22. 



Mcnibranipora rossellil, McG., P.Z.V. 26; A. hnrmrmm, McG., T.b'.S.V. ; 

 July, 188G. 



Zoarium encrusting or loosely adnate. Zoceeia elongated, quadrate, with 

 prominent crenulated margins; about two-thirds of the area filled in l)y a thin 

 calcareous lamina; aperture with the lower edge usually oblique, but sometimes 

 straight or irregular. 



S.P. Living. Victoria. 



Closely allied to the recent A. rossellii, from Avhich it differs in the shape of 

 the zooocia. In recent specimens the aviciilariuni, wliich I have not seen in the 

 fossils, is very peculiar ; it is situated in a special cell, the mandible narrow below, 

 broad and exjianded above and directed upwards. Avicularia have not been 

 observed in A. rossellii. Failing these, it is difficult to say whether the two are 

 specifically distinct, as the difference in the zowcia is scai'cely sufficient to rank 

 them as such. 



3. A. arethusa, D'Orbigny, sp. PI. V., fig. 21. 



Eschara arethusa, D'Orbigny. P.F.T.C., j). 127; Membra^iipora arethusa, 

 Waters, Q.J.G.S.. Aug., 1883, p. 434. 



