When her best friend moves away, Amy feels bereft: ``I wish there were hundreds and hundreds of Mary Anns,'' she tells Daddy, imagining that it wouldn't matter, then, if one moved away. At that point, she's diverted by finding a praying mantis. She names it Mary Ann, keeps it in a terrarium, and faithfully gives it live food. As Mama has gently foretold, the insect dies after laying her eggs; but weeks later, while Amy and her parents are enjoying a reunion at her old friend's new house, the eggs hatch. The screen is off the terrarium, so when the family comes home their house is full of ``hundreds of Mary Anns.'' The friendship and the natural history lesson are worked seamlessly together in James's simple, direct text, which is ably complemented by sunny illustrations that nicely convey the warm relationships and add such intriguing details as how the screen was dislodged. A note offers sensible advice on keeping a mantis. (Picture book. 4-8)