have her granddaughter with her this summer, and I was very glad because the Mowbrays have gone abroad, and I expected to have them to play with. Now we can pair off; you and I can go together and Mary can go with Grace Wharton. I don't suppose," she added after a minute, "that it would be quite polite always to have it that way, for Mary is our own cousin and we can't shove her off on a stranger."

"Maybe we shall not want to," said Polly. "If she is real nice, Molly, we won't mind taking turns, or we can all three play together when the Wharton girl isn't there."

"But don't you ever, ever tell that I said I wasn't sure of wanting Mary," said Molly impressively.

Polly promised, and just then they were called to luncheon and went down-stairs with their arms around each other.

CHAPTER III

Mary

A week later the family was settled for the summer in Miss Ada Reid's cottage by the sea. In front of them was a stretch of green; beyond were the jagged rocks, and then came the ocean. The landing was some distance from the cottage and was upon the bay side of the peninsula, so, although Polly had caught glimpses of the sea during her journey, she did not have a clear view of the wide expanse until they had nearly reached the house and the great blue ocean spread out before her. Then she danced up and down with sheer joy.

"It is just as big and just as blue as I thought," she cried. "Oh, I am so happy! I am so happy!"

Molly was delighted at Polly's enthusiasm, for she, too, loved the sea and the rocks and the wide stretches of grassy hummocks. "There is the cottage," she told her cousin; "the one peeping over that little hill. It looks just like a brownie, doesn't it, with its surprised window-eyes? I always call the cottage 'The Brownie,' and Aunt Ada says it is a very good name for it, because it is a sort of brown."

"I should call it gray," said Polly.

"It is really gray, but it is a sort of brownish gray, and anyhow I like the name of Brownie for it. There is Aunt Ada on the porch watching for us."

Miss Reid came running out to meet them. She gave Molly a hug and a kiss and then turned to her other niece. "And this is our Polly, isn't it?" she said. "Bless the dear; I am so glad to see her. Come along in all of you; I know you are as hungry as hunters and I have dinner all waiting."

"Oh, Aunt Ada, is there to be baked mackerel?" asked Molly.

"Yes, and lobster salad, too."

"Are the wild roses in bloom yet, and are the wild strawberries ripe?" queried Molly.

"The strawberries are trying to get ripe, but I haven't seen a single wild rose yet. Come right in; I know by Dick's eager look that he is ready for my baked mackerel. I have Luella Barnes to help me this year," she whispered, "and she has a big white satin bow in her hair because we have a young man as guest." She laughed mirthfully and Polly thought the way her eyes squeezed up was perfectly fascinating. Her Aunt Ada had visited Colorado when Polly was a baby, but, of course, Polly did not remember it, nor would her aunt have recognized her baby niece in the little rosy-cheeked girl before her.

"This is something like our house," said Polly, looking around with a pleased expression at the unplastered room with its simple furnishings.

"Then you will feel at home," said her aunt. "Take off your hats, girlies, while I see to dinner, for you know the necessity, Molly, of looking after things yourself up this way."

Just here Luella appeared. She was a tall, angular young woman with a mass of fair hair, very blue eyes and a tiny waist. The white satin bow was conspicuous, and as she caught sight of Dick Reid she simpered and giggled in what the little girls thought a very silly way since it displayed Luella's bad teeth to which she evidently never gave the least attention. However, they all soon forgot everything but satisfying their appetites with the baked mackerel, deliciously fresh, the roasted potatoes, young peas and lobster salad.

"These taste so different from canned things," said Polly, passing up her plate for a second helping of lobster.

Luella reached out a bony arm and took the plate. "I'm glad to see you can eat hearty," she remarked. "Give her a real good help, Mr. Reid."

Molly giggled, though she knew the ways of the "hired help" her aunt employed in the summer. Aunt Ada gave her a warning look, for the natives were quick to take offense and Miss Ada had no wish to be left with no one in the kitchen. "And when is Mary coming?" she asked.

"Oh, we don't know exactly," Molly told her. "Mother will bring her up when she and papa go to Rangeley. Mother thought it would be in about a week. What will you do with three little girls to look after, Aunt Ada?"

"Oh, I expect them to look after me," returned Miss Ada.

"And if they don't do that properly, or if they get obstreperous," put in Uncle Dick, "it is the easiest thing in the world to throw them overboard. I'll do it for you, Ada; the rocks are very handy, and it will not be much of a job."

Polly made a face at him. "I know how much you'll throw us over," she said. "You'd better not try it with me, you sinful evil-doer."

"You see what is before you, Ada," said Dick. "You'll rue the day you consented to have three nieces with you for a whole summer; yet," he shook his head and said darkly, "I know what can be done if worse comes to worst."

"What then, Mr. Dicky-Picky?" said Polly.

"That's for me to know and for you to find out," he replied.

"My, ain't she sassy?" said Luella in a loud whisper to Miss Ada, "but then he ain't no more'n a boy the way he talks."

This was too much for Dick who could not keep his face straight as he rose from the table quickly. "Who's for the rocks, the cove or the woods?" he asked.

"The rocks, the rocks, first," cried both little girls.

"I want to show Polly the dear little pools where the star-fish are, and the cave under the rocks where we found the sea-urchins and where those queer bluey, diamondy shining things are," said Molly.

Polly squeezed her hand. "Oh, I'm so excited," she said. "I have been just wild to see all those things."

"You shall see them in short order," her uncle told her. "We keep our aquarium in the front garden."

"Where is the garden?" asked Polly innocently.

Her uncle laughed as he led the way over the hummocks down the rugged path to the rocks. Here they clambered over crags and barnacled boulders till they came to a quiet pool reflecting the blue of the sky. Its sides were fringed with floating sea-weeds and it was peopled by many sorts of strange creatures which thrived upon the supplies brought in by the ocean with its tides. A green crab scuttled out of sight under some pebbles; a purple star-fish crept softly from behind a bunch of waving crimson weeds; a sea-anemone opened and shut its living petals; by peering under the shelving rock one could see the dainty shell of a sea-urchin.

Polly gazed astonished at the pool's wonders. "It is like fairy-land," she whispered. "I never saw anything so beautiful. Can we come here every day and will the little pools with these queer creatures always be just this way?"

"We can always come at low tide," Molly told her.

"Then I'll always come down here at this time every day."

"But it will not be low tide always at this time," said Molly.

"Oh, won't it?" returned inland little Polly, quite taken aback. "Why won't it?"

Then her uncle told her how the coming in of the tide changes just as the rising of the moon does, and that one must know the difference in time to be sure. Then he went on to explain something about the small creatures which inhabited the pools, the barnacles which covered the rocks up to a certain point.

"Why don't the barnacles go any higher?" asked Polly. "I should think they would grow and grow just like grass does over bare