279 
European species referred by tbe late Prof. De Koniiiok to tbis genus do not wholly 
accord with those for which it was originally ^Droposed by the late Dr. Meek. It is 
possible that the same objections can be raised against the Australian shells.* 
CniENOMrA ? EtheeidCtEi, I)e Koninch, sp. 
Sangainalites Etkeridgei, De Koninck, Foss. Pal. Nouv.-Giilles du Sud, 1877, Pt. 3, p. 262, t. 17, £> 2 
(non t. 16, f. 2). 
Sp. Char. Shell of medium size, gibbous, curved, more or less oblique, and pro- 
duced posteriorly ; flanks very gibbous in the visceral region, rapidly decreasing to 
the ventral margin. Cardinal margin or hinge-line less than the length of the shell, to 
some extent curved upwards ; ventral margin somewdiat obliquely curved from before 
backwards. Anterior end subtruncate ; posterior end obliquely and abruptly truncate, 
with a narrow gape. Umbones anterior and prominent ; diagonal ridge rounded ; 
posterior slope flattened. Lunule apparently elongated and narrow; escutcheon 
wide, and moderately long. Lines of growth rugged and coarse, with intermediate 
flner striso. 
Ohs. The specimen from which the above characters are taken is rather 
Crushed, and they are therefore open to modification. The diagonal groove represented 
in Do Koninck’s figure is not visible in the present example. It is a much longer species 
than Chmnoniia ? acuta, Etheridge, and the dorsal margin appears to rise rather more. 
In specimens of O. JStheridgei from the Maitland Coal Measures the diagonal ridge varies 
much in its development ; in some it is very' pronounced, in others but little apparent, 
liow much of this is due to pressure and distortion it is difficult to say, but in some 
specimens it undoubtedly is the case, as it is accompanied by a greater or less degree 
of artificial iuequivalvism ; but in all such cases the wddth of the valves is much 
increased, as if by pressure from above. 
Loc. and Horizon. Banana Creek, near Banana, Dawson Eiver {II. Machay ; 
Colin. De Vis) — Middle or Marine Series, Bowen Eiver Coal Field; ? Gympie (W. II. 
Rands) — Gympie Beds. 
Chjjnomta ? CAKiNATA, sp. nov., PI. 43, figs. 5 and 6. 
Sp. Char. Shell rhomboidal, short, oblique, gibbous, produced posteriorly, 
highly carinate. Cardinal margin short ; lunule short and wide ; escutcheon moderately 
wide and shallow, with sharp margins ; ventral margin obliquely rounded. Anterior 
end small, very oblique ; posterior end obliquely truncate, slightly gaping. Diagonal 
ridge very marked, prominent, and sharp ; posterior slope concave, with a median groove 
or depression. Umbones prominent and terminal, incurved. Concentric ridges very 
coarse and widely separated, ending at the diagonal ridge, or but very little marked on 
the posterior slope. 
Ohs. These characters are taken from a decorticated specimen. This is a very 
marked shell when viewed in profile, from the great prominence of the diagonal ridge. 
When seen from above, across the valves, its great width at once attracts notice, being 
quite two-thirds the length of the shell. The short form, and the wide, highly 
carinate condition, without any sign of distortion, lead me to regard this as a distinct 
species. 
Loc. and Horizon. Banana Creek, near Banana, Dawson Eiver {H. Machay ; 
Colin. De Vis) — Middle or Marine Series, Bowen Eiver Coal Field. 
* They certainly are not SanrjuinoUtes, as that genus was restricted by De Koninck (see p. 281). I 
hope to work the groups out shortly. (B.E. Junr.) 
