32 
Observations. — This species bears a general resemblance to Aviciilo- 
l>eclen Ilardmani, Etli. fil./ but we believe it to be distinct from this North 
Australian form. There is here no sign of ecbination on the costcC of 
D. loingenensis, which is quit(> distinct from any other New South AValcs 
Dclfopecten. 
Locality and Horizon. — rortion 110, Tarish Wingeu, County Brisbane 
iC. Cullen ). — Permo-Carboniferous — Upper Marine Series. 
Collection . — ^Mining and Geological Museum. 
DeLTOI’ECTEN OELIQUxVTUS, nov, 
(Plate XI IT, Fig. 7.) 
Specific Characters. — Shell (cast) obliquely and unsymmetrically 
oval, produced posteriorly. Left valve moderately convex ; dorsal margin 
considerably shorter than the width of the valve ; umbo acute ; anterior 
slope abriq)t, but a gently graduated posterior slope ; anterior auricle large, 
flat, triangular, the outer margin ol)li([uely rounded, cmarginatc at its 
junction with the valve ; posterior auricle moderately large, Aving-like (outer 
margin not preserved). Sculpture consisting of [)rimary, secondary, and 
tertiary costa*, obliquely curved on the posterior side; a secondary costa 
exists between every two primary, and a tertiary on each side the former, but 
ajiparently very short ; traces of both latilamiua* and transverse concentric 
lines are apparent. lTinge-])late linear, grooved Avith resilium furroAvs, 
ch on d r o j) h o r e s m a 1 1 . 
Ohscrralions. ~'\:\\\% is a v(*ry marked form, (piite distinct from any 
other Australian sjiecies. Only the left vah'c is knoAvn, in the cast condition, 
the auricles in this state being unornamented. The outline indicates an 
approach to those forms termed by the late Prof, dames Hall Pterinopecten. 
Locality and Horizon . — Porter’s Bay, Tasmania. — Permo-Carboni- 
ferous. 
Collection. — Mining and Geological Museum. 
f. 4-8. 
' Etheridgo, Junr. — Coiitrib. I’al. S. No. '.) ( S, Aus(r. Pari. Papers, 1897, No. 127), p. 15, t. 1, 
