236 ON SOME MESOZOIC FOSSILS FROM CENTRAL AUSTRALIA, 



materials, to which the color of so many of the European green 

 sands is due. It is owing in that case, to a peculiar green deposit 

 in the chambers and cells of Foraminifera, while in the Australian 

 rocks, there are no Foraminifera and very little lime. The green 

 color is due to small fragments of a material which I believe to be 

 opaque hornblende. There is some admixture of iron pyrites, and 

 a good deal of brown coal and fragments of coniferous wood mixed 

 with fossil remains, but there are no notes to show whether they 

 occurred in distinct bands or were indiscriminately mingled with 

 the rest. 



The fossils contained in this collection, comprise : One fine 

 specimen of the guard of a Belemnite, which I regard as identical 

 with Belemnites australis. Moore.* Some valves too imperfect for 

 satisfactory identification, but not unlike Cucullcea inflata. Moore 

 (loc. cit. p. 250). Also fragments of a large Cyprina. (C. expansa 

 Etheridge? Jour. Geol. Soc. 1872, p. 338), a Mya, Tellina, and 

 finally numerous large and well-preserved specimens of Avicula 

 with characters which belong to many of the species described by 

 Moore, besides a single valve of a species of Trigonia which is 

 certainly undescribed. I shall proceed to consider these fossils in 

 detail. 



Belemnites australis, Moore (loc. cit. Plate XVI. figs. 1, 2, 3, 4, 5.) 

 Guard hastate, with a rather long, very slightly undulating outline, 

 ventral face flattened but without a trace of a ventral groove ; two 

 lateral grooves sharply cut and approximating to the ventral face 

 in the alveolar region, thence bending towards the dorsal aspect 

 with a scarcely perceptible curve and continued in a fine stria on 

 the ventral margin. The specimen is broken round the alveolar 

 cavity, but the extreme length of what remains is 145 millim. 

 w r idth at the alveolar end 20, greatest width at the end of the 

 lateral groove, and about the centre of the fossil 22, ventro-dorsal 

 width greatest at the broken end, and gradually tapering thence to 

 the point. 



* Quart. Jour, Geol. Soc. Lon. 1870, p. 261. 



