Now, it is easy to become overwrought about the heavy social import of these things, but let us consider the mail order seed catalogue as one of the great and relentless leaveners of our American life and times.

The rite of the catalogue is as certain as spring itself. Its arrival amid winter drear presages new season and new life. It appeals to the agrarian genes, admit it or not, that all of us carry. Its offerings, reviewed and considered night after night, incite fancies of prodigious gardens and flame the vain quest for the earliest tomato in the neighborhood. Placement of the first order is, in another sense, everyman's affirmation of faith in continuity, future and life itself.

For all this, the seed catalogue is an umbilical to the past.

Seed and nursery listings go back to the Colonial 1730s, but the birth of the mail order seed business in the mid-1800s is attributed to Benjamin K. Britt, a Massachusetts seedsman whose name belongs in any pantheon of entrepreneurial capitalism. Others sold over the counter; Britt decided to turn to the mails.

His idea was perfect for its time and place. The frontier was expanding rapidly; subsistence farmers and homesteaders were moving westward; their access to mercantile establishments was limited. Seeds by mail was a natural for rural America.

LISTEN TO Alan E. Fusonie: "The catalogue was an emerging method of capitalism, a democratization -- all people could find and afford the catalogues. The availability of land and the ability to get it created a whole new market. But once the settlers got out there, they were alone. Rolvaag's Giants of the Earth told us of that loneliness. The seed catalogue broke that loneliness.

"With the type of society we have today, we have very little patience; we don't have time. But the seed catalogue allows us to stop, look and listen. It allows us to continue a bondage and a linkage with the many generations who went before us. It is about as American a document as there is . . ."

Fusonie knows about these things. As the National Agricultural Library's archivist and historian, Fusonie oversees one of the country's biggest unheralded treasures -- tens of thousands of antique seed and nursery catalogues, some more than 200 years old.

To pass an afternoon perusing the NAL collection in Beltsville is as glorious as it is humbling. Glorious, because the catalogues tell a ground-level story of the American horticultural dynamism of more than a century ago. Humbling, because they often are far more sophisticated than today's state-of-the-art color-splashed and gimmick-laden catalogues.

What more, for example, can be said about a 1793 broadside, circulated in Richmond, hawking "a choice collection of flower roots, & seeds, Just Imported."? It went this way:

"MINTON COLLINS, most respectfully informs the ladies and gentlemen of Virginia, that he has just received by the ships Grand Duke and Birmingham, from London, a fresh assortment of the following SEEDS & FLOWER ROOTS, which he is now selling for ready money, at his Seed and Flower store (ONLY) north side of the Main Street, between the Post-office and the Bridge; where Country storekeepers may be supplied with an assortment, upon moderate terms."

Collins' brochure listed more than 100 varieties of grass and vegetable seeds, flower roots and seeds and "100 other sorts too tedious to mention." He also offered an assortment of white glass bottles, flowerpots and other garden supplies, as do most of today's catalogues. Remember, this was 1793.

A footnote put things in perspective. "As M. Collins intends to confine himself entirely to the seed business (having a very particular friend in London in that line, who will keep him constantly supplied with the best of all sorts) he hopes that, with his best endeavors to please his customers will entitle him to a preference."

T HE LANGUAGE changes, but today's catalogue publishers say much the same thing. There is constant grappling for a piece of the vegetable seed business, which accounts for something more than $300 million in annual sales. Actually,says Nona Koivula of the National Garden Bureau in Willowbrook, Ill., more seeds are sold over the counter than by mail.

But, she agrees, the catalogue has special magnetism. "It goes way back. It was the only way to buy seeds, and especially to find the new varieties, because there was no other way to merchandise. That fascination has been handed down from generation to generation . . . The catalogue is important, a unifying family thing to sit down together and pick out the seeds for the spring garden," Koivula says.

The bureau counts 73 seed companies in the mail order business, which is on an upswing as Americans turn more and more to the mails for all manner of merchandise. Fifteen of the 73 seed mailers have appeared on the scene since 1983 and the catalogue trend is toward specialization: tomatoes, beans, herbs and salad greens. "The age-old way of marketing, like Sears did it, was to have a big variety of things in the catalogue," Koivula says, "but even that is changing."

Today, of course, no catalogues are alike, and just as one company specializes in varieties, another aims its appeal toward a certain audience. The Vermont Bean Seed Co., a relatively new firm in Bomoseen, Vt., does both with an artistic old-timey bean-dominated catalogue aimed at an audience that president Guy A. Thomas calls "hard-core gardener."

In its own way, Vermont Bean Seed's success is writ in the image of old Benjamin Britt. Thomas went into business in 1974 with a simple mimeographed sheet listing bean seeds, the only thing he sold. This year, with a catalogue of more than 60 pages, Thomas sent out 1.4 million copies with a postage bill of $130,000. From 2,000 orders in its first year, Vermont Bean Seed now handles 1,000 orders a day from January through April.

Another of the premier catalogues comes from Johnny's Selected Seeds in Albion, Maine. Unlike any other, Johnny's catalogues contain detailed cultivation data that become a daily reference for most customers. "We operate on the idea that a thousand words is better than one picture," says Johnny's founder, Rob Johnston. "Our attitude is that the customer has the ability to understand what he is getting . . . In general, there is a trend to make the catalogues more glossy. And some have come with more and more color from the larger, more popular companies. I don't see that. Most catalogue retailing condescends to the customer. We've never taken that attitude."

Johnston's rule works well, for him at least. From a beginning in 1973 with a catalogue of 24 pages mailed to about 1,000 customers, Johnny's this year sent out 300,000 catalogues. "It's like getting a free magazine, and most people enjoy that," he says. "We like to think we're getting a growing list of people who are fascinated by reading these things."

Fascination is the word. Horticulturist Corinne Willard of Wethersfield, Conn., has looked at thousands of catalogues as part of her business and as part of a history she's writing on the seed business.

"With the catalogue, it's all right there in front of you, not like a radio or television ad. It is the stuff people dream of; they're looking for something new. It's a continuing unraveling of horticulture," she says. "Part of the enchantment comes from a catalogue like Mellinger's an Ohio firm with thousands of helter-skelter listings . You find new things each time you look at it. Was there a golden age? We're in a golden age of catalogues, period. But I think the heyday of the seed catalogue was before the turn of the century. The idea was novel; many people were starting gardens, and the catalogue was the only way they could get the seeds they needed."

A word from the past is appropriate. It comes from a section of the 1852 catalogue of Comstock, Ferre & Co., a Wethersfield seed firm that has been owned by the family of Willard's husband since 1871.

"In undertaking to get the start of your neighbors," Comstock counseled, "you will be likely to sow some of the tender seeds too early. If you do, and are disappointed in their not coming up, don't fret about the seeds, but try again: Seeds are cheap."

How little we've changed.