There's lots of them in Markdale, and that's the reason, he says, why they always have such good clover crops there." "What on earth have old maids to do with it ?" cried Cecily.
"I don't believe they've a single thing to do with it, but Mr.Roger says they have, and he says a man called Darwin proved it.

This is the rigmarole he got off to me the other day.

The clover crop depends on there being plenty of bumble-bees, because they are the only insects with tongues long enough to--to--fer--fertilize--I think he called it the blossoms.

But mice eat bumble-bees and cats eat mice and old maids keep cats.

So your Uncle Roger says the more old maids the more cats, and the more cats the fewer field-mice, and the fewer field-mice the more bumble-bees, and the more bumble-bees the better clover crops." "So don't worry if you do get to be old maids, girls," said Dan.
"Remember, you'll be helping the clover crops." "I never heard such stuff as you boys talk," said Felicity, "and Uncle Roger is no better." "There comes the Story Girl," cried Cecily eagerly.