‘A(j 
F1S8ILUNULA Clakkei, Moore, sj). 
(]>1. YI, Fig. 3 ; PI. IX, Fig. 1 ; PI. X, Figs. 1 and 2 ; PL XI, Figs. 1 ami 2.) 
CytherCd cierkel, IMoore, C^uart. Joum. Geol. Soc., 1870, XXVI, p. 250, 1. 13, f. 1. 
Cyprina expcinsa, Ftheridgo, Quart. .Tonrn. Geol. Soc., 1872, XXYIIl, p. 338, t. 19, £. 1. 
Cyihcrea Claricei, Eth. fiL, Cat. Austr. Foss., 1878, p. 108. 
Cyprino expansa Etli. flL, Cat. Austr. Foss., 1878, p. 108. 
Cythercci Cl<(rJcei, Tate, Proc. Austr. Assoc. Adv. Sci. for 1888 (1889), 1, p. 230. 
Cyprinci Claricei, Eth. til., Geol. Pal. ()’laud., &o., 1892, pp. ITl and 5G8, t. 20, f. 18 aud 19, 
t. 27, f. 9 aud 11 (? f. 10). 
Sp. Chars . — -Shell oyate-tvapozifomi, iullated and very inequilateral. 
Cardinal margins eonvex tlironghout ; ventral margins fully rounded. 
Anterior ends protnherant and compressed ; posterior ends at first tumid, but 
gradually losing their tumidity towards the posterior margins, which arc 
rounded. Umhonal regions high, prominent ; anterior slopes short and 
concave, hut without diagonal ridges ; posterior slopes long, flattened, and 
with inconsjneuous diagonal ridges. Anterior adductor scars less marked 
than the posterior, irregularly oval ; anterior pedal scars small, immediately 
above the adductors ; posterior adductor scars longitudinally oval. Pallial 
sinuses remarkahly shallow. Sculpture of concentric lamina and intermediate 
lineations, the edges of the laminte sometimes enriched with delicate, faint, 
longitudinal denticulations ; on the anterior slopes and ends are transverse 
puckerings arranged in longitudinally curved lines ; general surface shining. 
Ohs . — These characters are supplementary to those given under the 
generic description. This widely-distributed shell is the largest and one of 
the most characteristic species of the Australian Upper and Lower Creta- 
ceous, and is usually met with in the form of ill-preserved internal casts and 
exfoliated specimens. AVhetlier or no there is more than one species, the 
present state of onr knowledge does not enable me to judge, but that some 
amount of variation exists amongst the specimens I have seen is undoulited, 
and it is by no means impossible that this variation may indicate separate 
specific identity. Indeed the much deeper pallial sinus, as seen in one of my 
own ligures,’^ would appear to bear this out. 
Loc. — AVellsinking, at a depth of eighty feet, eight miles east of 
Alilparinka, Xorth-AA"est X. S. AVales {IFarden C. King) ; well, at a depth 
of one hundred and fifty feet, Alount Stuart East Block, about eight miles 
' (Jt'ol. .'uul I’al. (,)’laiid, 1892, t. 27, f. 9>. 
