"You see, sir," said the skipper; "oysters ain't fit to eat except in certain months.  They are only prime from October to March.  In April they begin to sicken, they are of a milky white colour, though fit enough to look at; then they become of a dirty grey colour, and then change to black by July, when they cast their spawn.  After this it takes them two months to get well again, and they ought to have another month to fatten up, which brings us to October.  It always makes me angry-like when I see people eating oysters in August; but there are poachers at all times ready to fish them up; and there would be many more if they were not sharply looked after.  It is a curious fact, that while the beds on the coast of Kent make very good nurseries for oysters, they do not grow as large and fat as they do on the Essex coast.  A little fresh water don't hurt them; but snow water kills them, as it does other fish, outright.  To most people, one oyster is just like another; but there are many different sorts, and each sort has a fancy for a particular place.  The oyster gives us work for most months in the year; for when not fishing to sell, we are either dredging up the young oysters or laying them down again."