276 
the margin obliquely curved downwards, posterior slope not manifest ; siphonal ridge 
slightly perceptible. TTmbones small, quite atiterior, and from them proceed four diagonal 
ridges, spreading out ventrally :• surface otherwise concentrically lined. 
Obs. The above characters are taken from a decorticated cast. From P. 
3Iorrisii, De Koninck, this species differs by having diagonal ridges confined to the 
centre of the valve. From P. hiplex, Do Koninck, by possessing four instead of two 
diagonal ridges, as well as a much straighten hinge, and a different outline to the 
posterior margin. P. Pandsi is undeniably nearest to the European P. costaitis. 
Brown,* * * § but in the latter the divaricating ridges are broken up, three on the body of 
the shell and the fourth under the hinge-line. 
Loc. and Horizon. Near Yarrol Station, Burnett {TV. H. Pands) Glympie 
Beds. 
Genus — ASTAPTPLLA, Hall, 1858.t 
(Iowa Geol. Report, Ft. 2, p. 715.) 
Astaetelua ? EHOMBOiDEA, sp. nov., PI. 14, fig. 15. 
Sp. Char. Shell small, square-ovate, compre.ssed; hinge-line much arched, very 
oblique posteriorly; ventral margin rotinded, anterior margin more inclined to be square 
thau rounded, whilst the posterior margin is decidedly square ; umbones prominent and 
projecting ; lunule probably well marked ; surface with sharp thread-like, raised, 
equidistant, concentric stri®, with more or less flat interspaces. 
Obs. The more important hinge characters of this shell are at present unknown, 
and its reference to Astartella is therefore purely suppositive. It possesses the 
sculpture of many species, but the hinge-line is too oblique for a true Astartella. 
It agrees better generally with certain forms described by the late Dr. Meek 
fi’om the Coal Measures of Ohio,j; than it does with Hall’s type, which is a more massive 
shell, although still small. 
The sculpture of A. ? rhomboidea resembles that of Pachydomus Panai, De 
Koninck, § but the shell otherwise differs completely in the outline of the posterior end. 
Again, it appears to have certain relations with the genus Scaldia, DeRyckholt, but the 
present name will, in the meantime, serve to distinguish it. It is certainly distinct 
from either of the New South AYales shells referred to this genus by Prof. De Koninck. 
Poo. and Horizon. G-ympie {R. L. Jade) — Gympie Beds. 
Genus— CYPPICAPDPLLA, Hall, 1858. 
Cypricarddla, Hall, Trans. Albany Inst., 1858, iv.. Ft. 1, p. 17. 
Microdon, Conrad [non Agassiz), Jonrn. Acad .'Tat. Sci. Fhiladelphia, 1842, viii.. Ft. 2, p. 247. 
Ctpeioaedblla .Iacku, sp. nov., PI. 14, figs. 11 and 12. 
Sp. Char. Shell oblong-ovate, nrodeiately compressed, deeper than wide ; hinge- 
line straight, horizontal; ventral margin ver/ oouvexly rounded; anterior side small, 
the margin obliqnely curved; posterior margin similarly curved, but not produced, 
umbones anterior, small, and inconspicuous ; escutcheon well-marked and deep ; lunule 
none, the anterior border being erect and simple ; surface nearly smooth, or with very 
fine impressed concentric lines. 
* King, Mon. Fermian Foss. England, 1850, t. 15, f. 13-20. 
t Aon Astartila, Dana, 1847. 
t Ohio Geol. Report, 1875, ii.. Ft. 2 (Fal.), t. 19, f. la and 5. 
§ Foss. Fal. Nouv.-Gallea du Sud, 1877, Ft. 3, p. 278, t. 19, f. 5. 
