OF NEW SOUTH WALES. 



conspicuous ribs, circular calico, an essential columella, exserfc 

 thick granular septa, and lobed pali. There were only two species 

 in this genus, and one dependant upon a single specimen. They 

 were always fixed upon a trochoid shell, which the tissue of the 

 coral almost completely closed round in the course of its growth, 

 and the only sign of its presence was the circular aperture 

 which was always left for the mollusc thus imprisoned. Subse- 

 quently Mens. M. Edwards discovered that one of the species, in 

 spite of its pali and sub-entire septa which closely resembled the 

 type of the genus in which it was placed, possessed synap- 

 ticulse, and should be separated, and placed in a distant family, 

 the FungidcB. Here, however, it was also out of place, because no 

 other genns of the family possesses pali. But the pali them- 

 selves are doubtful. They are lobed, and so are the septa, and 

 indeed hardly distinguishable from them. In 18-50 Mr. J. E. 

 Gray added what he considered a third species to the genus. 

 This was Heterocyathus hemisphericus, described in the Annals of 

 Nat. Hist for 1850 (Second Series, Vol. 5, p. 410.) It was 

 brought from the China Seas, and was thus described : — Corallum 

 extremely short, four complete cycles ; septa unequal, primaries 

 very thick, especially near the columella, the next in extent are 

 the fourth order, then the secondaries, then the fifth order 

 then the tertiaries, which are smaller than all the others, 

 all very close, but little raised, and the border feebly 

 arched. The two latter species have been erected into two 

 genera. One Psammoseris, which is thus characterised : Corallum 

 of trifling height, fixed on a shell which it completely encloses, 

 except at the peristome ; wall thick, bare, strongly granular, and 

 scarcely striate beneath ; columella papillary, septa scarcely 

 prominent, thickly covered with very projecting granules, 

 penultimate cycle more developed than the last, and approaching 

 each other before the last. I confess that this description does 

 not appear very clear. The words in French are as follows : — 

 " Celles (doisons) de Vavant dernier cycle heaucoup plus developpSes 

 que celles du dernier et rapprochees entre elles au-deva7it de ces 

 dernieres.^ It would seem as if the third cycle was larger than 



