290 A. W. TTATEES OX CHILD S'lOilATOTrS BRYOZOA FEOiE 



with a large nnmber of species it would be extremely difficult to 

 say whether they should be placed iu Memhninipora or Amphi- 

 hlestrum. We see in A. pajjiTlatum^ Busk, that it really has a thick 

 border extending inwards, and not a plate, as in Membranipora 

 Rosselii. As the genus Memhranipora is so large, and contains 

 such a variety of forms, it is to be hoped that other characters may 

 be found to separate this genus more definitely. 



Loc. Liying: Queenscliff, Williamstown, and "Western Port 

 {MacG.). Possil : Aldinga and Eiver-^Iurray Cliffs, 



14. MiCEOPOEA (?) PATTJLA, Waters. (PI. YII. fig. 4.) 



Micropora patula, Waters, Quart. Journ. Geol. Soc. vol. xxxvii. 

 p. 326. 



Steganoptorellapatula^'Wa.ters, Quart. Journ. Greol. Soc. vol. xxxviii. 

 p. 265, pi. ix. fig. 31. 



A specimen from the Eiver-Murray Cliffs, in the Lepralia-stage, 

 is much better preserved than the one from Curdles Creek or Mt. 

 Gambler, and has below many zooecia a zooecial (?) avicularium, 

 surrounded by an almost circular border, within which is the man- 

 dibular area, also surrounded by a granulated border, which is at 

 the lower end narrow, but at the distal end becomes very broad. 

 The avicularian opening is small and slit-like. Above the oral 

 aperture there is a small ovicellular opening. The ovicell is scarcely 

 at all raised, and would certainly be overlooked if it were not for 

 this small opening; but in some cases the front wall is broken 

 away, and then the ovicell-chamber is distinctly seen. At each 

 side of the ovicellular aperture there is a depression or opening. 



A similar supraoral opening has been figured in Membranipora 

 semiaperta, Eeuss, EscharineTla muraJis, Gabb & Horn, JReptofius- 

 trina JieterojDora, G. & H., and Cellepora Mohli, Hagenow. 



Loc. Curdles Creek, Mt. Gambler, Eiver-Murray Cliffs. 



15. MiCEOPOEA PEEFOEATA, MacG. 



Memhranipora perforata, MacGillivray, Trans. Phil. Instit. Yiet, 

 1859 ; iSTat. Hist, of Yict. decade iii. p. 29, pi. xxv. fig. 2. 



When speaking of var. clausa, Waters (Quart. Journ. Geol. Soc. 

 vol. xxxviii. p. 505), I pointed out that Monoporella Zepi(^«, Hincks, 

 was allied to M. perforata, MacG., but they must be separated, either 

 as varieties or species, on account of the much more fully developed 

 avicularium of M. lepida, though the position and direction of the 

 avicularium is similar. From jN^apier, IS'ew Zealand, there are spe- 

 cimens of M. perforata without avicularia, and others in which the 

 small avicularium described by MacGillivray is pretty constant. In 

 many zooecia in these Napier fossils there are several pores, as in 

 recent M. lepicla, from IN'ew Zealand ; whereas in the Aldinga fossils 

 it is rare to find more than the two below the aperture. The zocecia 

 of the Australian fossils are very regular ; but those from !N"apier 

 show great variation in this respect, and therefore it is very pro- 

 bable that Steganoporella eJongata, Hincks, is only a synonym. 



