FOSSILS OF NEW SOUTH WALES. 687 
bending over the postero-dorsal margin. Beak none. Surface smooth, with some faint 
concentric undulations and lines of growth.—Length 1% inch; height 43, L.—Plate 2, 
fig. 10, exterior cast of a valve, natural size. 
Harper’s Hill. 
No palleal or muscular impressions are distinguishable. 
Solen (Solecurtus 2?) planulatus, Expedition Fossils, Amer. Jour. Sci., i. Ser., iv. 153. 
17. PHotapomya (Pratymya) unpATA (Dana).—Equivalve or nearly so, transverse, 
inequilateral, compressed, subelliptical, thinning to an acute edge in front, somewhat pro- 
longed and narrowed behind; sides flattened; flank obliquely truncate and subcarinate 
without. Cardinal area linear, circumscribed. Surface smooth, with a few large irregular 
concentric undulations, which are crossed, especially below, by faint radiations.—Length 
3,) inches; height 7, L.; thickness ;4;, L.; distance of summit of beak from anterior 
margin 33, L.; apical angle 138°.—Plate 2, fig. 11, @, 6, views, natural size. 
Wollongong Point, [lawarra. 
The specimen is an external cast; the beak projects about an eighth of an inch above 
the cardinal margin. The palleal impression is not seen on the specimens in the collec- 
tions, of this or either of the three following species, and we cannot say whether it has a 
sinus or not. We suspect the latter, in which case the species are not Pholadomyz, and 
may be near the Meoniz. 
Pholadomya undata.—Expedition Fossils, in Amer. Jour. Sci., ii. Ser., iv. 153. 
18. PHorapomya (Homomya) GLENDONENSIs (Dana).—Oblong, inequilateral, subin- 
flated, in front subacute (acute?) ; posteriorly prolonged and becoming quite thin; flank 
not carinate, Surface concentrically subplicate and striate, not at all radiate ; plice 
unequal, and passing into strice of growth. Lateral surface not at all flattened—Length 
about 2# inches ; anterior part more than half the posterior.—Plate 2, fig. 12 ; specimen 
much broken. 
Glendon, valley of the Hunter. 
19, Pootapomya (Homomya) aupax (Dana).—Ventricose, oblong, very inequilateral, 
subequivalve, the left valve larger ; thick in front and truncate, and a little concave near 
the margin; posteriorly prolonged and thinning and narrowing, a little recurved, gaping. 
Umbos large and prominent, inflated, incurved, contiguous, Lateral surface strongly 
flattened or subexcavate obliquely downward anterior to middle. Surface longitudinally 
plicate, and marked posteriorly with obsolete radiations ; plications smooth, low and 
rounded, the alternate towards the middle becoming obsolete, and all obsolescent near 
posterior margin.—Length 47 inches; height 5%3, L.; thickness #7, L.; the anterior 
part hardly { L.—Plate 3, fig. 1 a, 6, c, different views, natural size. 
Illawarra, Wollongong Point. 
This fine species differs from the following in having the beaks more prominent and 
the left largest ; also in the posterior extremity diminishing more in height, the flank less 
inflated, and the front more abruptly truncate. There are about twenty-four plications on 
the anterior half. The cardinal area is hardly circumscribed, and the flanks are not 
flattened. 
Allorisma audax, Exped. Foss., Amer. Jour. Sci., ii. Ser., iv. 153. 
