60 
M. T. WARNE 
was further complicated by Bonaduce et al. 
(1980) who included specimens attributed to the 
type species of Polycopsis in Metapolycope. 
tion with palaeodepth, group 1 species tending 
to be more abundant in deeper-water facies than 
group 2 species (Warne 1987). 
Genus Polycope Sars, 1866 
Type species. Polycope orbicularis Sars, 1866. 
Polycope sanctacatherinae Whatley & Downing 
1983 6 
Remarks. The five Polycope species described 
herein fall into two morphological groups. 
Group 1, which is characterised by narrow inner 
lamellae, no division of the muscle scars and 
relatively strongly ornamented carapaces, 
includes P. sanctacatherinae Whatley & 
Downing, 1983, P. melbournensis sp. nov. and P. 
sp. A. Group 2, characterised by broad inner 
lamellae, division of the posterior and dorsal 
scars in some specimens and weakly orna¬ 
mented carapaces, includes P. thomasi sp. nov. 
and P. warneetensis sp. nov. Group 2 species 
also have greater valve overlap in the dorsal 
region and thicker hinge elements than group 1 
species. These two groups show a broad correla- 
Figs 1A, 2A-D 
rotycope sp.—McKenzie 1974: 160, pi. 1, fig j 
Polycope sanctacatherinae Whatley & Downin. 
1983: 387-388, pi. 8, figs 20-21.-Wamc 1987*44, 
pi. 1, fig. A. 
Holotype. Adult RV, OS 121000 from the Fvansford 
Formation (Middle Miocene, Balcombian) at Fossil 
Beach, Momington, Victoria; housed in the Micro¬ 
palaeontology Section, Department of Geology, Uni¬ 
versity College of Wales, Aberystwyth. 
Additional material. One hundred and three disarticu¬ 
lated adult and juvenile valves from the Fvansford and 
Sherwood Formations. 
Fig. 1. A, Polycope sanctacatherinae Whatley & Downing, 1983, LV internal, NMVP122191,x 122. ft, Polycope 
melbournensis sp. nov., RV internal, NMV PI22195, paratype, x 90. C, Polycope sp. A., LV internal.NMV 
PI22200, x 116. D, Polycope thomasi sp. nov., LV internal, NMV PI22196, holotype, x 130. E , Polycope 
warneetensis sp. nov., LV internal, NMV PI22198, holotype, x 85. F, Polycopsis? sp. A., RV internal, NMV 
P122201, x 81. A-C from Fyansford Formation (Balcombian), Fossil Beach, Mornington; D from Fyansford 
Formation (Balcombian), Batesford Limestone Quarry; E, F from “Warneet Sands” (Cheltenhamian or 
Kalimnan), Geological Survey of Victoria Sherwood 18 borehole. 
