Vol. XXVII. 

 igio. 



1 Chapman, Silurian Fossils of South Yavva, &-c. 67 



PELECYPODA (bIVALVES). 



Y. Grani'inysia abbreviata, Chapm. 



Ref. — Chapman ('08), p. 14, pi. i, fig. 2. 

 Also in the Yeiingian series, south of Mansfield. 

 Y. Palcuanatiiia, cf. solenoides, J. Hall. 



Ref.— Chapman ('08), p. 18, pi. I., fig. 6. 

 Y. D. Edmondia perobliqua, Chapm. 



Ref.— Chapman ('08), p. 18, pi. I., figs. 7-9. 

 A moderately common fossil, and apparently restricted to the 

 locality. 

 Y, Cardiola cornucopice, Gold fuss, sp. 



Ref. — Chapman ('08), p. 20, pi. I., figs, it, 12. 

 An interesting species on account of its wide distribution. 

 Found in Great Britain, from the Llandeilo (Upper Ordovician) 

 to the Upper Ludlow (Upper Silurian) beds. The British 

 specimens are recorded under the name of 6'. interrupta, Sowerby, 

 but the specific name given here has priority. In Victoria this 

 species is also found at Moonee Ponds Creek. 

 Y. Ctenodonta portlocki, Chapm. 



Ref.— Chapman ('08), p. 24, pi. II., figs. 17-20. 



This species has also been found in the Yeringian series near 

 Lilydale. 

 Y. Nuculites coarctatus, Phillips, sp. 



Ref.— Chapman ('08), p. 26, pi. II., figs. 24, 25. 



The shells of this genus are readily distinguished from other 

 Nuculacea by having an anterior buttress or muscle-support on 

 the internal surface of the shell, seen in the casts as a distinct 

 slit. Cucullella, often referred to on the old geological quarter 

 sheets, is a generic synonym. /V. coarctatus also occurs near Mt. 

 Disappointment. 

 Y. Nuculites maccoyianus, Chapm. 



Ref. — Chapman ('08), p. 25, pi. II., figs. 21-23. 



Also found at Merri Creek and Yan Yean. 

 Y. D. Nucula melbournensis, Chapm. 



Ref.— Chapman ('08), p. 28, pi. II., figs. 29-33. 



One of the commonest of the Silurian bivalves, and practically 

 confined to the Melbourne area. 

 D. Nucula arcce/orinis, Chapm. 



Ref.— Chapman ('08), p. 30, pi. II., fig. 36. 

 Y. Nucula taylori, Chapm. 



Ref.— Chapman ('08), p. 30, pi. II., figs. 37, 38. 



Also found at Broadhurst's Creek, near Kilmore. 

 Y. Nucula opima, J. Hall, sp., var. australis, Chapm. 



Ref.— Chapman ('08), p. 31, pi. III., figs. 39-43- 



Also at Yan Yean. 

 Y. D. PalcBoneilo victoy^ice, Chapm. 



Ref.— Chapman ('08), p. 33, pi. IIL, figs. 47-49- 



An ornate form, often showing the remarkable toothed, 



