14 
THE GEELONG JTATURALIST. 
perceptible. If the shell be well washed, the growth will take the 
marking of a pencil well, and it will be found that the oyster is 
generally in the fifth or sixth year before it is fit for sale. 
The food of the oyster consists of very minute organisms which 
some experts call animal, some vegetable ; and those who are of a 
microscopic turn of mind will add to the general store of knowledge 
if they will take the trouble to examine and report on the contents 
of an oyster's stomach. The oyster's mouth is situated between the 
delicate folds of what is ordinarily called the beard, i.e.^ the 
breathing organs, and by following down the course of the gullet, 
the stomach can easily be found embedded in the thick part of the 
body of the oyster, which is really the liver. 
Oysters may be divided into two classes — the natives and deep 
sea; between these there are several varieties. The points of an 
oyster are: — first, the shape, which, to be perfect, should resemble 
the petal of a rose leaf; second, the thickness of the shell. A 
native should have a shell like a thin china tea-cup. It should have 
also a metallic ring, and a peculiar opalescent lustre on the inner 
side. The hollow for the meat of the oyster should be as much like 
an egg-cup as possible. Third, and lastly, the meat itself should be 
white and firm, and nut-like in taste. 
I omitted to mention when writing of the enemies an oyster 
has to contend against, that it has also its friends. Periwinkles are 
friends to oysters, and are largely employed to keep the beds and 
*'culch" clean, by eating up the slimy, green weed that grows so 
abundantly, especially in hot weather. Mussels are no friends to 
oysters. A colony of mussels will, unknown to the proprietor of 
an oyster bed, often settle upon the "sperm gregis" of "half-ware,'* 
so carefully deposited to grow and fatten. I would here remark 
that there is no real "fat" in an oyster; to fatten oysters is, there- 
d'ore, an expressive but not correct term. One thing I would advise 
my readers to do, and that is, never to allow the oyster to be served 
to them on the flat shell, but always on the round shell, with the 
natural liquor left in the hollow. This liquor is not sea water, but 
contains much of the same chemical ingredients as the oyster itself, 
•and is usually thrown away as useless. 
The following is an analysis of the meat of the oyster: — 
1st — Water containing hydrochlorate of soda — hydrochlorate 
■of magnesia — sulphates of soda, lime, and magnesia. 
2nd — Much phosphate of iron and lime. 
3rd — Much omazone and glycogen. 
4th — A certain quantity of gelatine and mucous. 
5th — An animal material of which phosphorous is the principal 
element. 
Western Port and Corio Bay years ago had their natural oyster 
beds. In the latter, the deposit of the silt from the dredges on the 
eastern and southern portions has, to a very great extent, destroyed 
valuable oyster breeding grounds, but from practical experience I 
