BOOK REVIEW : A Tell-All About the Sex Lives of Insects : BROADSIDES FROM THE OTHER ORDERS: A Book of Bugs <i> by Sue Hubbell</i> ; Random House $23, 288 pages

I would love to have been a fly on the wall--pardon the expression--when the publisher of this “book of bugs” discussed its marketing program.

Knowing that “Broadsides From the Other Orders” was being released at the start of the summer reading season, the publicity staff showed great restraint in not playing up one of the book’s most conspicuous subjects--sex.

Forget the historical romances, the latter-day bodice-rippers, the thinly veiled novels about lascivious glitterati: the characters in Sue Hubbell’s book are an equally passionate, even kinkier lot, and so what if they, in flagrante, have a dozen or more legs?

Take a certain Parnassius butterfly, which Hubbell encountered a few years back while hiking the Wyoming Rockies as part of the annual Fourth of July Butterfly Count.

“This is one of the most fascinating things in all invertebrate biology,” an entomologist tells her, having just netted the insect in question. “ Parnassian females mate only once, because after the mating, the male secretes a fluid that solidifies and forms a structure called the sphragis around the female’s reproductive opening.”

In other words, instant chastity belt . . . but one with a major drawback, for should the male attempt copulation for much longer than the three hours necessary for the fluid to harden, he may end up, in the words of the scientist, in coitus perpetuus .

Male dragonflies have a different problem, which is that their external sexual organs are closer to their heads than their tails, where they are located in the female dragonfly and in most insects. To mate, consequently, the male must use his tail to grab the female by the back of the head and curl her body and tail beneath him.

Entomologists refer to this posture as the “wheel position,” the insects forming a squashed circle, but the casual observer will likely note that it resembles a pose illegal for humans in many states.

Another oddity among dragonflies is that although their enormous eyes give them generally keen vision, they have trouble distinguishing objects directly in front of them.

A male may inadvertently attempt to mate with another dragonfly’s shadow, for example, and the Smithsonian Institution has taken note of an incident in which a dragonfly latched onto a ruby-throated hummingbird.

The bird survived, but it’s anynbody’s guess whether the dragonfly was pursuing eros or dinner.

Food and sex often go together in the bug world, as any adolescent--having learned in biology class that female praying mantises may make a meal of their sexually spent mates--will tell you.

But Hubbell, a New Yorker magazine contributor whose previous books are “A Country Year” and “A Book of Bees,” stays well away from such familiar territory, and that’s one reason “Broadsides” is instructive as well as entertaining.

Most of the 13 chapters, each an essay, deal with insects we see every day but know little about: water striders, daddy longlegs, midges, katydids, camel crickets, gypsy moths, hover flies and their kin, and it’s startling to learn what complex and interesting lives they lead (even discounting their methods of procreation).

If you’ve ever seen wormlike creatures marching en masse through a forest in a line up to 15 feet long--what a sight that must be!--chances are you’ve come across fungus gnat larvae, traveling for reasons as yet unknown.

And next time you’re tempted to squash a silverfish into oblivion, spare that old (biologically speaking) gray head: “The greased pig of bugdom” may eat the glue holding your books together, but it eats house dust, too.

Most of the chapters in “Broadsides” are engrossing, but the one on ladybugs will fascinate even insectophobes. Hubbell goes into the Sierra with a pair of professional collectors who have learned just where the beetles hide out during the hot summer.

In a single day, Hubbell and the “buggers” collect more than 2 million ladybugs--about $600 worth, to be sold by mail (sometimes after months of refrigeration) to commercial and backyard gardeners. The manager of perhaps the largest ladybug supplier in the world, based near Sacramento, tells Hubbell that her clients “just insist on ladybugs” despite her attempts to talk them into buying an even more ferocious aphid predator, the green lacewing.

Most bug books are aimed at children, those of us who have yet to lose their sense of wonder. It’s a great pleasure to come across an adult--sometimes very adult--bug book, one that reminds this reader, at least, of why he spent so many youthful hours on hands and knees.

I’m quite sure I’ll refer to “Broadsides” when my own children grow older and ask permission to turn the playroom into a bug zoo.

How else will I be able to prove to skeptical visitors that marshmallows are indeed appropriate insect food and that certain larvae thrive best on rabbit droppings (moist, not wet)?

Unlike Hubbell, I’ll spare you further details, just in case you’re still at breakfast.