448 R. ETHERIDGE, JITN., ON AUSTRALIAN TERTIARY ECBINODERMS. 



and posterior pair are continued beyond the petaloid portions by 

 separate pairs of impressed pores (fig. 11). The ventral grooves 



Figs. 11 and 12. — Micraster brevistella, Laube. 



11 



Fig. 11. Micraster brevistella, Laube, dorsal surface, showing ambulacral ar- 

 rangement, nat. size. Banks of the Murray river, South Australia. 

 12. Oral aperture of the same, nat. size. 



radiating from the mouth, and which correspond to the ambulacra 

 on the dorsal surface, are distinctly pored, the posterior pair the least 

 so, and the anterior pair the most so (fig. 12). The madreporiform 

 body is badly preserved, but still may be seen occupying the centre 

 of the apical disk. 



Loc. — Banks of the Murray river ; Blanford Collection, M. P. G., 

 1. specimen. 



Genus Monostychia, Laube. 



MONOSTYCHIA AUSTRALIS, Laube. 



M. australis, Laube, I. c. p. 190, fig. 3. 



Clypeaster folium, Duncan (non Agassiz), Annals Nat. Hist. 1864, 

 xiv. p. 166. 



A comparison of the form referred to by Prof. Duncan as C. folium, 

 in his paper on Australian Tertiary Corals, with Dr. Laube's descrip- 

 tion and figures of M. australis, has convinced me they are one and 

 the same. For an opportunity of comparing the specimens I am 

 indebted to the Council of the Geological Society. 



Loc. — Mount Gambier, in the Coralline Limestone : Coll. Geol. 

 Soc. Lond. Murray Cliffs : Jukes Collection, M. P. G. 



I have to tender my best thanks to the Council of the Geological 

 Society for the loan of specimens in the Society's collection ; and to 



