18 Mr. A. W. Waters on Australian Bryozoa. 



many spatulate avicularia. Ovicell distinct, raised, but partly 

 buried in the cell above ; its surface is perforated. 



It is very difficult to know where this should be placed ; 

 but the appearance and the general characters are decidedly 

 those of ISmittia^ as is also the thin operculum ; but there is 

 no lyrula, and the sinus would make it ScMzojporella. Smittia 

 ohstnicta has a semicircular chitinous bar, and a bar also 

 occurs across the operculum of Lepralia mucronata, 13. ; but 

 this is not a common character. 



Smittia ohstnicta^ sp. nov. (PI. III. figs. 7, 8.) 



The surface of the zoa3cium is granular, the sides of the 

 peristome are very prominent, and sometimes there is a short 

 triangular avicularium leaning against each prominence, the 

 lower edge of the peristome is continuous, but not much 

 raised. 



Ovicells distinct, slightly elevated, proximal and distal 

 portion thickened by a subsequent calcification, forming a 

 perforated area between. Two or three suboral spines. 

 Sometimes a fairly large avicularium on the front of the 

 zocecium, and there are a few spatulate vicarious avicularia. 



The operculum is characteristic, being marked by a 

 thickened crescentic ridge starting from each lower corner ; 

 the rest of the operculum is thin. Lyrula distinct, not large. 



This may be the Smittia trispinosa var. bimucronata of 

 Hincks. 



Retepora Jissa^ MacG. 



Betepora fssa, MacG. Trans. Roy. Soc. Vict. vol. ix. p. 140; ib. vol. 

 xix. p. 2iJl, fig. 8 ; Zool. Vict. dec. x. p. 17, pi. xcv. figs. 12-16. 



There is a young colony from Green Point without ovicells, 

 and many of the zooecia are unarmed, but some have avicu- 

 laria. Two radical calcareous processes are thrown ofi', and 

 there is often a triangular avicularium at the base of the 

 fenestra. A young colony like this is with difficulty distin- 

 guished from R. avicularis. As mentioned in my Suppl. 

 ' Challenger ' Eeport, it would seem that R. Jissa may be made 

 the centre of a group. 



Reiepora porcellanea^ MacG. 



For synonyms see Waters, Suppl. liep. on the ' Challenger ' Polyzoa, 

 p. l9. 



Rlnjncliopor a 'profunda^ MacG. (PI. II. fig. 15.) 



Hhynclwpora profunda, MacG. Trans. Roy, Soe. Vict. vol. xix. p. 19.3, 

 pi. ii, fig. 8; Waters, Ann. & Mag. Nat. Hist. ser. 5, vol. xx. p. IOC, 

 pi. vi. figs. 11, 16. 



