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



19. Cellaria gracilis (Busk). (PI. IV. %. 6.) 



Salicornaria gracilis. Busk, Brit. Mus. Cat. p. 17, pi. Ixiii. fig. 3 ; 



' Challenger ' Eeport, p. 93. 

 Cellaria gracilis, MacGillivray, Zool. Vict. dec. v. p. 50, pi. xlix. fig. 4. 



Some fragments from Raton are without avicularia, and 

 then it is difiScult to distinguish between C. Johnsoni, B., and 

 C. gracilis, B. ; but the large semicircular opening of the 

 ovicell, often with a verj distinct lip, agrees with specimens 

 from Holborn Island, and, I think, enables it to be separated 

 from G. Johnsoni, B., with certainty, as this last has smaller 

 elliptical openings. There are Cretaceous fossils from Maes- 

 tricht &c. which, in the zocecial characters, are allied to Cel- 

 laria, although thej were erect and unarticulated. The solid 

 branching Escharella argus, d'Orb., has an aperture of the 

 Cellarian shape, with four teeth, just like Cellaria crassa, 

 and the ovicell is also concealed in a similar manner. Refer- 

 ence to Escharipora rJiomhoidalis, d'Orb., will also show the 

 relationship. I have previously pointed out that the young 

 branches of Cellaria at first have the calcareous wall continu- 

 ous with the parent joint, and the chitinous articulation is 

 formed subsequently ; but as some correspondents were unable 

 to verify this, I can only suppose through lack of suitable 

 material, I give a figure taken from a photograph. 



This can, however, readily be seen in C. Jistulosa and any 

 of the common species. 



I have pointed out (p. 89) that this is by no means confined 

 to Cellaria, but occurs in other articulated species, and supports 

 the idea that articulated forms are derived from unarticulated 

 ones. 



In the Crag and other Pliocene formations of Europe C. 

 crassa is found with the branches continuous, or, as Mr. Bask 

 says, with a tendency to ossification, which does not seem a 

 fortunate method of indicating what takes place, as we must 

 not suppose that there has ever been a joint. 



Loc. Cumberland Island ; Cape Capricorn ; Victoria ; 

 Station 186, 8 fath. (Torres Straits); Holborn Island; off 

 Raton, New Guinea, 7 fath. 



20. Farcimia oculata (Busk). 



Nellia oculata, Busk, Cat. Mar. Polyzoa, p. 18, pi. Ixiv. fig. 6, pi. Ixv. (bis) 

 fig. 4 ; ' Challenger ' Report, p. 27 ; Smitt, Floridan Bryozoa, p. 3, pi. i. 

 figs. 53, 54 ; Haswell, Polyzoa from Queensland, p. 3t3 ; MacGillivray, 

 Zool. Vict. dec. v. p. 51, pi. xlix. fig. 5 ; Hincks, Journ. Linn. Soc, 

 Zool. vol. xxi. p. 121. 



This was placed at first by Busk in the family Cellariidte ; 



