TEN DAYS IN the Yucatan didn't leave me yearning for more Mexican food. But after three days back home I was already sentimentalizing, thinking which of the dishes I'll keep in my repertoire as souvenirs.

Above all, fruit abounds. Hotels all offered breakfast buffets with large thin slices of sandia (watermelon), pina (pineapple), melon, guava and platanos (stout but sweet bananas). Mayan women on the street, brown and broad, wearing white cotton dresses with colorfully embroidered yokes and hems, called out the names for the fruits they sold in nasal voices: papayas, mangoes, breadfruit, limes.

In M'erida, the Yucatan's capital city, it seems that every block of the town's center is graced with a juice stand. Called Jugos California, these stands offer salvation in hot midday, or any time of day when one dares not slake one's hunger with anything too unknown. Fresh tropical fruits line the walls of these little storefronts. You will find whole pineapples, whole guavas, piles of oranges (greener and tarter than any we know), piles of limes, and apothecary jars with papaya and guava already cut into manageable chunks. Three sorts of licuados or drinks are sold: jugo, straight juice; con agua, thinned out with ice and water; and con leche, with milk. Only the pulpier, less acid fruits are mixed with milk: guava, papaya, breadfruit.

Jugos are made to order, either in hand-pressed juicers for citrus and pineapple, strained before serving, or in blenders for the thicker drinks. Order a jugo de pina and down comes a pineapple, knifed, rind and all, into fist-sized chunks, then wrung through the hand-juicer.

Certain rules of thumb have to be learned about jugos. My first order was for straight papaya, remembering my old favorite, Papaya King on 86th Street in New York City. "Con agua?" the clerk asked, and now I know why. I could barely get a straw down through that straight papaya juice. A few days later I asked for pina y naranja--pineapple and orange, an expectable choice, it seemed to me. The clerk screwed up her forehead a little, but went along with the idea. Another customer told me that no one would choose it there: too acid. Considering the sourness of the oranges used, I had to agree. Most pleasing combinations: naranja y papaya and platanos con leche.

And always the ubiquitous lime. Everything is served with limes, from the breakfast fruit platters to cervezas in the sunset. A can of cheap light beer comes adorned with a salted lime, and limes are tossed into jugos. The blender spins with papaya and ice. Then half a lime, rind and all, goes in for the last split second, just to add an edge. A plate of limes comes with almost every entre'e, certainly with every seafood meal. The limes are sliced differently than what we are used to: parallel to the stem-to-blossom axis, but off-center. One presumes that the central section remaining from each lime is reserved in the kitchen for cooking.

But in contrast with the abundant fruit, vegetables were hard to find. Mayan women sell vegetables on the streets, but only a small assortment of them. Only two varieties of tomatoes were to be seen: those we would call pear tomatoes, small, oval, and pulpy; and another pinker, star-shaped variety, appearing equally pulpy. In restaurants, most often one finds vegetables used as condiments: a chunky salsa of tomatoes, onions and peppers; pickled slices of red onion; undressed cabbage slaw; and the inevitable basket of warm tortillas. One cuts chunks of the main course off and fills a tortilla with them, tops it off with what condiments look best, tucks the tortilla around the concoction, and then dips it into another sauce--the ultimate in finger food. Restaurants that tried to extend their vegetable offering--one wonders whether in response to American visitors--covered one corner of the plate with a gray pile of overcooked carrots, potatoes and turnips. One restaurant in Cozumel, which proudly showed a menu with not a word of Spanish on it, promised that your meal came "with rice and one vegetable." When it arrived, the vegetable was mashed potatoes.

Judging not only from restaurant fare but also from the cattle we saw grazing the roadside at a government demonstration farm, Yucatan beef is nothing to write home about. The dry, rattly plants they feed on don't seem to put much meat, let alone fat, on those bones. And you can be sure that Yucatec farmers don't waste maize on their cows.

If you want meat protein, you can order seafood: filete de pescado, often snapper or grouper; camarones or mid-sized shrimp; or, at seaside places, various interpretations of caracol or conch. Inland, many entre'es are made of chicken, including the indigenous and sometimes delicious condiments: plain by our standards, but plentiful, and good.

The northern stretch of the Yucatan peninsula is not a pretty place to see, though there are some exceptions: the skyline of M'erida, the underwater imagery among the Caribbean coral reefs. One does not go to the Yucatan to gaze on natural beauty, but to wonder at the cultures, at the traces of a civilization of intellect and energy, now dwindled down to village life, almost as primitive as it was before that civilization thrived.

Vacations are supposed to make you glad to be back home, and my digestive system agrees. I'm thankful for tasty tap water, for raw vegetables, for crisp salads all year round, for thyme and rosemary, even for the all-American hamburger. I'm thankful for an eyeful (and a mouthful) of life elsewhere, but I'm also glad I can bring their recipes home with me. Here are a few I found that are easy to prepare back home. SOPA DE LIMA (Lime Soup) (4 servings)

Almost every Yucatan restaurant had its own version of this interesting soup, a chicken stock spiked with refreshing lime. The most tasty version included bite-sized chunks of lime, rind and all, floating in among the chicken meat and tortillas, but limes I have purchased stateside were too bitter to follow that technique. 1 onion, minced 1 large tomato, minced 1 sweet green pepper, minced 1 tablespoon butter 4 cups vegetable or chicken broth 1 chicken breast, boned and cut in bite-sized pieces 2 uncooked tortillas, cut into chip-sized pieces 2 tablespoons cooking oil 2 limes

Cook vegetables in melted butter, adding them to the skillet in the order listed. Bring broth to simmer in saucepan and add vegetables to it, along with chicken meat cut into small pieces. Cover until ready to serve.

When ready to serve, quick-fry tortillas in oil and drain on paper towels. Slice each lime into 6 slices parallel to blossom-stem axis. Bring soup just to a boil, ladle into each soup bowl, float tortillas and 2 lime slices in each.

Reserve four end-slices of lime; use one for each soup bowl and squeeze juice into the soup as you serve it. Serve immediately. CEVICHE (Marinated Fish Salad) (4 to 6 servings)

Green salads were hard to find, but this marinated fish salad was served everywhere. Inland, most often it was made with mero or grouper. On the coast one could choose ceviche de caracol, or conch salad, too. The dominant flavor is the cilantro, available fresh in Spanish, oriental and farmers' markets: a soapy, herby green, the leafy part of the coriander. Dried cilantro can be substituted or (if you can't quite accustom yourself to the herb's flavor) fresh chopped parsley can stand in as a bland alternative. 3 lemons 1 lime 1/2 teaspoon salt Dash of sugar 1/2-pound fresh fish fillet 1/3 cup chopped onions 1/3 cup chopped green peppers 1/3 cup chopped tomatoes 1 chopped hot pepper 1 to 2 tablespoons fresh cilantro Lettuce for serving

Juice the lemons and lime; add salt and sugar to the juice. Cut the fish into small pieces and submerge it in the lemon-lime juice for 3 hours. During the last half hour, add the other ingredients to the marinade. Serve cold on a bed of lettuce. CAMARONES AL MOJO DE AJO (Shrimp drenched with garlic) (1 serving)

Not only shrimp, but also chicken, fish fillets and conch were served al mojo de ajo (drenched in garlic sauce). A strong garlic butter is prepared on the side, the fish or meat is broiled, then the two are combined. Proportions listed are for each serving. 2 cloves garlic 2 tablespoons butter 8 to 12 mid-sized cleaned shrimp (may be broiled with or without shells)

Mince garlic into fine pieces. Melt butter and saute' minced garlic in it. Spread shrimp on a broiler pan. Drain enough butter from garlic to drizzle over each shrimp. Broil 5 minutes. At the same time, give the garlic a final toasting until it just turns golden brown. Arrange shrimp on the plate and drench with toasted garlic.