B--Xestoleberis lilydalensis, Chapm. Silurian (Yer.) Victoria C--Argilloecia acuta, Jones and Kirkby. Silurian (Yer.) Victoria D--Bythocypris caudalis, Jones. Silurian (Yer.) Victoria E--Primitia reticristata, Jones. Silurian (Yer.) Victoria ] The largest ostracod yet described from Australia, measuring more than a quarter of an inch in length, occurs in the Upper Silurian of Cliftonwood, near Yass, New South Wales. It belongs to the genus _Leperditia_ (_L. shearsbii_), and is closely related to _L. marginata_, Keyserling sp.; which occurs in strata of similar age in the Swedish and Russian Baltic area. A limestone at Fifield, New South Wales, probably of Silurian age, contains _Primitia_, _Kloedenia_, and _Beyrichia_. =Devonian Ostracoda.--= The little _Primitia cuneus_ (Fig. 113 A) with a bean-shaped carapace and median pit or depression occurs somewhat frequently in the Middle Devonian Limestone of Buchan, Victoria. Another species, _Primitia yassensis_, is found in the shaly rock of Narrengullen Greek, New South Wales. It is probable that many other species of the group of the ostracoda remain to be described from Australian Devonian rocks. =Carboniferous Ostracoda.--= In Queensland a conspicuous little ostracod is _Beyrichia varicosa_ from the Star Beds of Corner Creek. =Carbopermian Ostracoda.--= In the Carbopermian of Cessnock, New South Wales, _Primitia dunii_ occurs; and in that of Farley is found _Jonesina etheridgei_. From both these localities _Leperditia prominens_ was also obtained. Another species from New South Wales is _Entomis jonesi_ (Fig. 113 B), described from the Muree Sandstone by de Koninck. [Illustration: =Fig. 113--UPPER PALAEOZOIC and MESOZOIC OSTRACODA.= A--Primitia cuneus, Chapm. Mid. Devonian. Victoria B--Entomis jonesi, de Kon. Carboniferous. New South Wales C--Synaphe mesozoica, Chapm. sp. Triassic. New South Wales D--Cythere lobulata, Chapm. Jurassic. West Australia E--Paradoxorhyncha foveolata, Chapm. Jurassic. West Australia F--Loxoconcha jurassica, Chapm. Jurassic. West Australia G--Cytheropteron australiense, Chapm. Jurassic. West Australia ] =Triassic Ostracoda.--= The Triassic (Wiannamatta Shales) of Grose Vale, New South Wales has afforded a few specimens of ostracoda belonging to _Synaphe_ (_S. mesozoica_, Fig. 113 C), _? Darwinula_, and _? Cytheridea_. =Jurassic Ostracoda.--= The marine Jurassic strata of Western Australia at Geraldton, have yielded a small but interesting series of ostracoda, largely of modern generic types. The genera, which were found in a rubbly _Trigonia_-Limestone, are _Cythere_, _Paradoxorhyncha_, _Loxoconcha_, and _Cytheropteron_. [Illustration: =Fig. 114--CAINOZOIC OSTRACODA.= A--Bairdia amygdaloides, G. S. Brady. Balcombian. Victoria B--Cythere clavigera, G. S. Brady. Balcombian. Victoria C--Cythere scabrocuneata, G. S. Brady. Balcombian. Victoria D--Cytherella punctata, G. S. Brady. Balcombian. Victoria ]