APPENDIX. 345 



And the genera whose characters it has been found requi- 

 site to modify are : 



Catenicella Cauda 



Salicornaria Emma 



Cellularia Acamarchis 



Scrupocellaria Caberea. 

 Bicellaria 



Of the twenty-four genera^ three, or perhaps four, 

 appear to be pecuHar to the AustraUan seas. These are : 



Calpidium Didymia 



Cauda ? Dimetopia. 



All the rest, excepting two, Emma and Diachoris, appear 

 to be distributed over the globe in both hemispheres. The 

 above two are perhaps limited to the southern. 



Of the fifty -three species, about thirty-three seem to be 

 new, or to have been so imperfectly described as not to 

 admit of precise identification, and five others have syno- 

 nyms more or less doubtful applied to them. 



Six species only are common to the seas of Europe, Adz. : 



Tuhulij)ora plialangea? Anguinaria spatulata 



Crisia denticulata Acamarchis neritina 



Eucratea chelata Retepora celhdosa. 



Sixteen others are met Avith in other parts of the Southern 

 hemisphere, viz. : 



Catenicella elegans? Catenicella cribraria 



ventricosa cornuta 



Eschara lichenoides, oc- Celhdaria monotrypa 



curring in Algoa Bay ; Bicellaria tuba^ in New 



Caberea Zelanica Zealand ; and 



Acamarchis tridentata, in Emma crystallina 



Algoa Bay and New Zealand; tricellata, in New 



Caberea lata Zealand and CampbelFs Is- 



Catenicella hastata land. 



Thus of the fifty-foui- species, about thii'ty-foui' would 



