BY PROFESSOR STEPHENS, M.A. 555 



like ft plateau. It is a phenomenon of much importance in con- 

 nection with the inquiries into the formation of the Hawkesbury 

 rocks, and the excavation of the Blue Mountain valleys. 



On the Edible Otsters found on the Australian and 

 Neighbouring Coasts. 



By J. C. Cox, M.D., F.L.S., &c. 



Some months ago I read before this Society a paper on the 

 Edible Oysters found on the Australian and adjacent Coast, and 

 exhibited specimens to illustrate my remarks. I stated that we 

 had five distinct species of Oysters on the coast of New South 

 "Wales 2)roper. Eirst the Mud Oyster — Ostrea Angasi, Sowb., 

 secondly the !Rock Oyster — Ostrea fjlomerata, Grould, third the 

 Drift Oyster — Ostrea suhtrigona, Sowb., all of commercial value ; 

 fourth Ostrea circumsiita, Gould, and fifth Ostrea virescens, Angas, 

 only of interest to the Conchologist. 



My paper as published attracted the attention of a critic 

 who is not only a successful commercial cultivator of our Oysters, 

 but who is a close and careful observer, and who has the preser- 

 vation and culture of our Oysters at heart for no selfish purpose 

 but as a public good. Mr. Woodward pointed out in the public 

 press that he thought I was wrong in considering our Eock 

 Oyster and our Drift Oyster distinct species, and founded his 

 conclusions from practical obserA^ations made by himself on his 

 Oyster Beds on the W^alambi at Cape Hawke two miles above 

 the village of Eorster. Mr. Woodward has recently paid a visit 

 to his Oyster Beds and has selected from four of them specimens 

 of Oysters for me to illustrate his reasons for differing with me, 

 and I now exhibit these specimens to you ; but instead of proving 

 to me that I am wrong these specimens have only the more firmly 

 convinced me that my theory of the replenishing of our exhausted 

 Oyster Beds is the correct and only one to be depended on. 



