Let us speak of blackflies.

Before I moved to Maine, blackflies, like scorpions and great white sharks, were merely a rumor. After nearly two decades of May, I now know better.

If you do not have blackflies in your neighborhood, you may be unaware of their habits. I will enlighten you. Blackflies are small creatures, about the size of those midges that go up your nose in late August. Unlike mosquitoes, which are surgically precise in their bloodletting, blackflies have mouths like chainsaws. Their favorite foods are roofers, toddlers in sandboxes, fans at middle-school baseball games, and crabby people who are planting beans. They will chew up any available part of these unfortunate bodies but are particularly fond of faces and the backs of ears. Signs that you have been bitten by a blackfly: crusty streams of blood and swollen eyelids. These symptoms are most likely to appear just before proms, poetry readings, graduation parties, and the visits of nervous grandparents from regions without blackflies.

One odd feature of blackflies is that they bite only in the open air. Any fly that accompanies you into your house immediately becomes disoriented and spends the rest of her life walking up and down a windowpane until the dog licks her up.

A blackfly's favorite weather is your favorite weather. Say, it's been 40 degrees and raining for 2 weeks. Then, suddenly, the sun emerges and the temperature rises to a delightful 70 degrees. Both you and the blackfly rush into the yard, eager to catch up on spring business. The blackfly's approach to business is lusty and sociable, and you soon find yourself indifferent to thinning radishes or raking gravel out of the lawn.

Yet even a blackfly's enthusiasm can wane. As soon as the heat increases to torpid summer, she shrivels and fades. At this point, the lurking deerfly becomes ascendent. That, however, is a tale for another day.