340 APPENDIX. 



Culcita Agassi z. 



This genus chiefly differs from Randasia and Pentaceros 

 in having no open series of marginal ossicules ; it agrees 

 with Randasia in the back being nearly flat. 



Culcita Schmideliajia. 



A. Schmideliana, Retz JDis. Schmidels. Naturf. xvi. 

 t. 1. (good) A. discoidea, Lam. 



Body subcircular,flat above when dry, (very convex, subglo- 

 bose when alive.) The back coriaceous, without any apparent 

 reticulations, covered with scattered small conical spines ; the 

 oral surface rather convex (when dry), closely and minutely 

 granular, and with larger conical tubercles, those near the 

 ambulacra and oral angles much the largest and ovate. 



Inhab. — Australia ? 



There are distinct indications of the lower marginal ossi- 

 cules in this species, but they and the ossicules of the oral 

 surface are not sufficiently large and close to force the dry 

 specimen to assume the pentangular form of the following 

 species. 



Culcita pentangular is, n. s. 



Body pentangular, back flat when dry, convex beneath, 

 minutely and closely granulated, back with obscure reticu- 

 lations, the reticulations armed with small conical tubercles, 

 the interspaces closely and minutely porous. 



The oral surface protected with distinct well defined 

 ossicules, defining the lower edge of the margin, closely 

 covered with minute granules, and larger round-topped 

 tubercles, those near the ambulacra and the oral angles 

 being largest and highest. 



Inhab. — Reef of Oomaga. 



This species is very distinct from the former, and forms 



