Birds and Nature Vol. 11 No. 2 [February 1902]. Various
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“Let us look at the dead oyster, Willis.”
“All right.”
Taking a toothpick in his hand he tried to turn over the oyster in the shell. He found that a thickened muscle near the middle part was fastened to the half shell. Tearing it loose he saw at this place a dark, purplish spot just like one on the other half shell.
“I wonder what makes that hard spot?”
“Oh, see, Joseph! Its body has two sides. The side lying in the deeper piece of shell is larger. Down the middle is a division and the edges come together something like the cover of a book. Over all is a white covering with such pretty frilled edges. See, I can roll it back quite a little way.”
“That is so. How pretty it is. It has no head. Does it eat? I wonder if it has a mouth.”
Willis searched carefully for an opening. At last he found one near the hinge.
“What is this?” asked Willis, handing his playmate a little doubled-up thing about as large as a pea.
After examining it carefully for a moment Joseph exclaimed: “You must have found its mouth. This is surely a baby crab which has been swallowed. See its little legs drawn up to its body.”
Both agreed that they had found a crab. They again turned their attention to the oyster’s mouth.
“What a large mouth for such a little animal! See how far I can put the point of my knife into it. It must have some bowels. I wonder if its bowels are here at the larger end. It looks puffy and dark inside. The thing is so slippery that I can scarcely handle it.”
“Can it see, Willis?”
“I can find no eyes.”
The boys took the oyster out of the water several times that they might see how it looked tucked so snugly between its shells. Every time they touched it the opening was closed tight. Thus the boys spent the afternoon.
When Joseph went home Willis said: “Come over to-morrow and we will get auntie to tell us more about the oyster.”
After dinner Willis went to his room and watched his oyster again until his eyes drooped.
Presently there was a thump-thump-thumping across the floor behind him. What was Willis’s surprise to see a big library book come near and with one leap place himself on the table. He was again surprised to see the oyster reach a long arm out of the water and the book another long arm from between its leaves. They two then shook hands. Both raised themselves to a vertical position and made a bow to Willis.
“We will try to tell you what you wish to know. Then you can surprise Aunt Jennie by telling her some things.” As he spoke Mrs. Oyster swelled herself up so large that the soft white matter protruded from the shell; for she had never before had the high honor of talking to a real boy.
Willis was so pleased that he clapped his hands.
Mrs. Oyster crawled up and nicely balanced herself on the edge of the dish. Willis was speechless with surprise.
Book spoke: “This is Mrs. Oyster. She belongs to the subkingdom of shellfish called Mollusca. All of her folks have soft bodies. As she is protected by a shell of two parts, she is said to be a bi-valve. Her relative, Snail,” said he, motioning with his hand, “having a single shell is called a uni-valve.”
Looking in the direction of the movement of Book’s hand, what was his surprise to see a snail with a shell on his back crawling across the table. Where he came from, Willis could not tell.
“When looking at that oyster this afternoon you noticed a thickened portion fastened to a dark spot on the valve,” said Book.
“I remember,” said Willis.
“There is a muscle,” continued Book, “fastened at the dark spot on each valve. It becomes very strong by use. An oyster knows how to let it stretch, thus opening the valves to allow water to enter his chamber. It also knows how to draw it up so as to close them to keep out intruders. The white covering over the body is called the ‘mantle’. If you notice the inside of an oyster valve, you can see a mark showing how near to the edge the mantle came. That is called the pallial line.
“If you will keep on looking you will succeed in finding that besides a mouth an oyster has a stomach, liver and intestines, a nervous system, and a heart that pumps blood, though it is not red but white blood.
“When you breathe, you take in your lungs from air what is called oxygen. Without oxygen there can be no life. Anything that can not in some way take in oxygen can not have life. Water as well as air contains it. Oysters have no lungs, but they have leaf-like gills on each side of the body. By means of these they get oxygen.”
“Can an oyster see?” asked Willis.
“It has organs of sight, hearing, smelling, touch.”
“Where are his eyes? We could not find them.”
“Hunt them again,” laughed Book. “I think that I will not tell you that. Since an oyster has no head you must not be surprised to find them in an odd place. The dark part which you noticed this afternoon and which shows so plainly in a cooked oyster is its great liver.”
“To-morrow I will again try to find eyes. Perhaps auntie will let me take her glass.”
Stepping near and pointing as he talked, Book continued:
“To protect her soft body, friend Mrs. Oyster’s mantle produces a shell of lime which grows by being enlarged around the edge. The high point on the left valve is called the beak. If you will scrub her shell with a brush to-morrow you will see lines running around the beak in the same direction as the margin. These are called ‘lines of growth.’ By them oystermen can tell the age of the shellfish.”
“How strange!” said Willis thoughtfully. “Tree trunks also show lines of growth.”
“Where did you come from?” asked Willis of Mrs. Oyster.
“As I have lived most of my life within this narrow shell,” she answered with a cast-down air, “I have no idea where I came from nor where I now am. Shall I tell you the story of my life?”
“Yes, do, please. It must be interesting. You are such an odd creature.”
“The first thing I remember,” said Mrs. Oyster after she had drawn a full breath, “is that I was a tiny bit of white mucus, or egg, as people say, swimming gayly around with my brothers and sisters in my mother’s shell. It was worse than in the case of the old woman who lived in a shoe. There were two or three thousand of us – maybe more. At any rate there were so many of us that our poor mother never had time to count us. But she was one who never worried. To keep us from getting lost she kept us in by closing her shell tight. That let her get no food. With a true mother’s spirit she fed us on the substance of her own body until she became very poor.”
“Beg pardon,” said Book. “Let me explain to our friend.