Cartoons illustrate down-and-out, mangy alley cats licking the inside of a sardine can while fat-and-happy cats sit on their master's lap and lust after the pet canary. Admit to enjoying sardines in America and you are treated like some sort of culinary pervert: They smell bad and they're cheap.

But a lot of people take sardines very seriously. They admire the way the thin silvery bodies are carefully packed head to foot, the grade of oil they are packed in and the type of fish used. So, in the interests of adding to the small coterie of sardine lovers in this time when cheap, nutritious food ought to be chic, we have gathered the following information. Sardine Definition

In 1966 a United Nations committee on fish decided in a week-long meeting that the term sardine should only be applied to small pilchards. The state of Maine, America's largest exporter of sardines, was not happy with this decision. Maine's sardines are baby herring. Neither were other commercial interests, so the U.N.'s attempt to narrow this Peter Sellers among fish products to a single identity didn't succeed.

In Norway sardines are really sprats (part of the herring family) and called brisling on the can. Sardines actually may be sild, sprats, herring or pilchard. Pilchard, which come from Sardinia, make the best sardines.

Sardine sales -- over $35 million a year -- mean more to Maine's economy than lobsters, because many lobsters really come from Canadian waters.

Sardines are one of the most primitive marine fishes because of their two-lobed nonfunctional lung. How to Catch a Sardine

Some fishermen in Spain's Galicia province allegedly use dynamite to blow up the fish, which are then skimmed into nets when they float to the top of the water. However, many Galician fishermen think this is cheating.

The U.S. Bureau of Commercial Fisheries in 1959 developed a one-inch plastic pipe, studded with little holes about a foot apart. The flexible tubes are laid along the bottom of the sea and compressed air is forced out of the holes. An air curtain is formed and used to drive schools of sardines into weirs. The sardines are removed from the net with a suction hose and stored in the hold of the boat.

According to Joseph Peleggi of the National Marine Fishery Service, sardines are usually caught at night when they rise to the surface to feed on animal plankton. The fish are phosphorescent and easy to see.

Maine fisherman, using planes, sonar, electronic scanners and depth recorders, spot schools in daytime.

Once caught, the sardines' scales are automatically removed by suction and used to make artificial pearls, cosmetics and lacquers. Snug as a Sardine

Canning methods vary from country to country. In France, Spain and Portugal the fish are dried, fried in oil and packed. In Scandinavian countries they are smoked and dried before being canned. Most of the larger sardines packed in Maine are cooked by steam.

Now to answer that burning question -- how do they get those little fish lined up in the can so neatly, laid head to foot? According to Gary Ray, of Maine's L. Ray Packing Co., it is all done by hand. He employs 100 women (men don't pack herring) who clean the fish, cut their heads off and put them side by side in the can. Jim Warren of the Maine Sardine Council explains why women are exclusively used as packers: "They have better finger dexterity. Men can't stand the gaff of the tedious work of cleaning, canning and packing." The average packer fills 2,000 cans a day and get paid per case. A fast, experienced packer can make up to $70 a day.

Cans of sardines go through a high-speed conveyor belt where oil or sauce is added. After the can is sealed it is submerged in a vat and sterilized. The finished cans are inspected for defects and, in Maine, a sample is sent to a state laboratory for inspection of quality, appearance and flavor. They don't inspect the keys. They should make sure every can has a key, and that the key will actually open the can. Sardine Diet

The secret of "Dr. Frank's No-Aging Diet Eat and Grow Younger," is to eat a lot of foods rich in nucleic acids, which make up DNA and Rna. Rule No. 1 says: "Four days a week, eat a 3- or 4-ounce can of small sardines."

Dr. Frank believes sardines have "a remarkable ability to lower cholesterol. Besides, they are lower on the food chain than bigger fish like tuna and are therefore less likely to contain man-made pollutants."

Dr. Frank's no-aging sardine diet didn't exactly catch on. People are still getting old. M.F.K. Fisher on Sardines

"Sardines in cans have a special quality which one either pines for or despises . . . I have eaten fresh sardines a few times and found them as different, but there is something mysterious that happens to a sardine can, quite beyond the expected fishy changes. I must admit to a flash of fondness now and then for the tiny ones, luxuriously packed and priced, and occasionally sent to me in a tuck box by rich uncles. I like to eat them when I am alone either straight from the can or with a toothpick or laid neatly, olive oil and all (it would be a pity to mash such exquisite little corpses), on a large diagonal slice of toasted French bread. This is perhaps coarse behavior on my part, but at least I do not like the coarser fish! They are too plump, too strong in taste and smell, too often packed in low grade oils or coated with erstaz tomato sauce. Horrors indeed! The truth is that I could live easily without any of them, even the wee ones . . ."