Tertiary Deposits Near Norseman, Western Australia, 95^ 
pectinids occur. The rock is very similar lithologically to the algal lime- 
stone at the southern end of Locality A. 
Among the more common fossils are Barbatia dissimilis Tate^ Cardium 
arcaeformis Chapman and Crespin, Venericardia sp., Chhmys murrayana. 
(Tate), and ChJaynys iddingensis (Tate). In addition the limestone con- 
tains two species of brachiopods and several species of gasti'opods, as yet 
unidentified. In samples from the same deposit Miss Irene Crespin has found 
twelve species of cheilostomaceous and cyclostomaeeous Bryozoa (see 
Appendix). 
Locality B consists of four disconnected outcrops on the lake-bed. On 
the northern shore of the bay the exposed thickness of the bed is tw'o to- 
three feet, elsewhere only one foot is visible. There is considerable lateral 
Text lig. 6. 
Limestone exposures on lake floor at Locality P>, on the Peninsula, Lake Cowaiu 
variation of species in these disconnected outcrojJH although they are prob- 
ably all of the same bed. About 10 chains from the southern headland of 
the bay is a ver\' fossiliferous limestone composed almost entirely of gastro- 
pods. After deposition the shells were dissolved, leaving cavities which 
have since been lined Avith crystalline calcite so that the external features- 
