PERMO-CARBONIFEROUS PELEOYFODA — ETHERIDGE. 
183 
between them and the dorsal margins the surface of the valves is 
somewhat hollowed, and before them are shallow ill-defined cinc- 
tures dying off towards the insinuated points on the ventral 
margins ; umbones inconspicuous ; anterior adductor impress- 
ions triangular, of medium size but strongly marked, deep 
anteriorly and superiorly, with well marked bounding grooves on 
the posterior sides ; posterior adductor impressions inconspicuous, 
flattened, placed high up under the hinge lines, and immediately 
at the ends of the dorsal margins : indications of scars exist within 
the umbonal cavities. Ligamental fulcral impressions wide and 
shallow; ligamental pits transversely elongated, eacli giving off 
an oblique and posteriorly directed ridge, and forming the anterior 
boundaries of the shallow cinctures. Pallial scars well marked, 
continuous (ie., not broken up), the surfaces below rapidly thining 
away o the ventral margins. 
Obs, — All the specimens are in the form of internal casts, as an 
impure somewhat concretionary limonite, allowance must there- 
fore be made in applying the above description to future examples 
with the test preserved. What the nature of this envelope was we 
are ignorant, but on a few of the specimens there are apparently 
faint indications of posterior radiating costre. An example from 
the Upper Marine Series of Wollongong, possessing the outline 
and measurements of this species, and with the test preserved, 
exhibits a few radiating posterior costae and strong imbricating 
lamime of growth that may represent the more perfect condition 
of S. farleyensis , but it cannot be accepted as by any means 
certain. 
Dana described two shells as Cardinia ? recta and C.? cnneata* 
both from the lilawarra District differing greatly in outline from 
those forms 1 have made typical of the new name Stutchburia , 
but the internal features depicted in his figures are precisely 
similar to those of S. farleyensis. They seem to be edentulous, 
and the only point allying them witli Cardinia are the nasute 
posterior ends. It is possible, therefore, that the shells in question 
may be species of Stutchburia , in which case the generic characters 
of the latter, will of necessity require to be slightly modified. 
The internal casts of S. farleyensis occur in great numbers in 
the Lower Marine Series at Farley, near West Maitland, and it 
is essentially a Lower Marine species, but the Geological Survey 
Collection contains a shell from the Upper Marine Series of 
Richmond Yale, Parish of Stanford, County Northumberland, of 
somewhat larger dimensions than the measurements above given; 
otherwise it agrees in every detail with my description. This 
bears out the suggestion that the shell found at Wollongong, with 
the test preserved is also S. farleyensis . 
* Dana — Wilkes 5 U.S. Explor. Exped., x., 1849, ph 4, f . 5 ci, b , and f. 6a - e. 
