126 EDIBLE OYSTERS POUTfD ON THE AUSTEALIAN COAST, 



while to attempt to cultivate so fine a species in its native 

 waters otherwise it is probable that it will soon altogether dis- 

 appear. The variety of it diagnosed by the Eev. J. E. Tenison- 

 Woods as 0. rutupina of Jeffrey's is still plentiful in some of the 

 Tasmanian waters. 



Ostrea edulis oi Linnaeus, is not recorded by Eeeve as being 

 found in any other locality except Europe, but he instances five 

 varieties as arranged by Jeffreys of it. 



1. 0. parasitica of Turton, adhering by a large part of its 

 under surface to shells &c. 



2. 0. hippopus of Lam, not gregarious like the ordinary form 

 but solitary, and living in deep water. 



3. 0. de for mis of Lam., including those varieties elongated 

 perpendicularly or laterally. 



4. O. rutupina of Jeffreys, a small regularly formed, not very 

 flaky variety, known as ''Natives." 



5. 0. tincta of Jeffreys, like the last regularly formed and flat, 

 but differing in having the sides coloured with purplish brown. 



It is difficult to understand why so able a monographer as 

 Eeeve has omitted to mention in any way the variety purpurea of 

 Hanley, either as a synonym of this species or any other, or 

 has not recorded it as a distinct species, which Mr. Angas 

 considered it. 



2. Ostrea subtrigona, Sowerhy. 



Figured in Eeeve's Conch. Icon., pi. xviii., sp. 38, fig. 38, a. b. 

 and described as follows: — "Shell subtrigonal, oblong or sub- 

 quadrate, ponderous, rather narrowed towards the umbones 

 broad at the ventral margin, quadrate ; margin strongly plicated 

 lower valve deep, greenish white, edged (slightly) with purple, 

 without radiately plicated, concantrically banded with fawn and 



