182 Mr. A, W. Waters on Australian Bryozoa. 



Membranipora reticulum, Pergens, Plioc. Bry. von Rhodes, Ann. k.-k. 

 Hofmuseums, Wien, Bd. ii. p. 14. 



A specimen from Palm Island has the zoarium in the Vin- 

 cularta-form, sometimes anastomosing, and, as I have pointed 

 out in a previous communication, it has " denticles " in all 

 the zooecia. Part of the colony has the zooecia surrounding 

 the stem of a seaweed, and in other parts the stem is solid 

 without any support. This is, as already shown, the Bi~ 

 Jlustra delicatula of Busk and MacGillivray. 



There is also a small fragment from Darnley Island, Torres 

 Straits, with a single row of zooecia on each of the four sides ; 

 the shape of the cells is similar to the above but not identical, 

 being more elongate, straighter, and somewhat larger, with 

 similar " denticles." It may be the Vincularia quadrilatera 

 of d'Orb. (Pal. Fr. p. 189, pi. 681. figs. 1-3), though from 

 so small a fragment it is impossible to speak with certainty, 

 so in the meantime I call it M. Savartu, var. quadrilatera , 

 d'Orb. (PI. IV. fig. 8). ^ 



Loc. Cretaceous, France ; Miocene, Austria ; Pliocene, 

 England, Italy, Sicily. Living: Florida, 29 fath. ; Victoria; 

 Queensland; Philippine Islands; Penang, &c. ; Palm Island, 

 N.E. Australia, 8-10 fath. 



27. Memhranij)ora corhula, Hincks. 



Membranipora corbula, Hincks, Ann. & Mag. Nat. Hist. ser. 5, vol. vi. 

 p. 378, pi. xvii. fig. 6 ; MacGillivray, Zool. Vict. dec. xiii. p. 103, 

 pi. 127. fig. 2. 



In a specimen from Shark Island the number of spines is 

 somewhat variable, there being sometimes two large spines 

 and three smaller oral ones. 



Loc. Victoria ; Shark Island, 8 fath., Sow-and-Pigs Heef, 

 Port Jackson, 3-4 fath., and Bottle-and-Glass Kocks, 8 

 fath., N. S. Wales. 



28. Memhrampora spinosa (Q. & G.) . 

 Membranipora spinosa, Waters, Quart. Journ. Geol. Soc. vol. xliii. 

 p. 48, pi. viii. fig. 32, for synonyms, and add MacGillivray, Zool. 

 Vict. dec. xiii. p. 107, pi. 127. fig. 8. 



In specimens from Vaucluse Point there is in the interior 

 what we may call a strengthening plate, at each side towards 

 the distal end, starting from the base of the zooecium, and 

 attached also to the border of the opesia. This I figured in 

 the fossil from Napier, where it is well marked and forms a 

 chamber on each side. 



The basal wall is only membranous, but in many cases 

 there is an oval space of thicker membrane or chitin. 



MacGillivray calls the spines rigid, and although this is a 



