"He don't look like all that much of a stud to me," muttered a vulgar fellow yesterday, observing the glorious London Zoo panda, Chia-Chia, who has come to Washington for heroic purposes.

There have been some embarrassing cases in which. after years of observation, it has turned out the boy pandas were girls, etc. The first panda in America was the exquisite little Su-lin (entered the Brookfield Zoo in Chicago in 1937) who, at a post-mortem, proved to be a male. An exquisite pale day lily, meanwhile, had been named in her honor, which would not have been done if anybody had known Su-lin was really a Marlboro type.

As most citizens of the capital know, we have two pandas right here, a male and a female. They have not thus bred. The London panda, Chia-Chia, went on display at the National Zoo's Panda House yesterday, and the idea is that maybe he will mate (the end of April or first of May) with our female, Ling-Ling.

"Now what odds would you give that we will wind up with a baby panda in due time?" the zoo director, Dr. Theodore H. Reed, was asked.

"This is a government building," he said, nodding to the pandas sitting on their haunches gazing about, "and as you know we do not gamble on government property."

Rectitude aside, we have a 75 percent chance of success, The Washington Post has learned from sources.

The London Zoo's Chi-Chi, a female, was diagnosed male by the distinguished scientists who observed her, but was determined to be female when examined under anesthesia. Likewise, the male, Chia-Chia, the very one on temporary duty at our National Zoo as a potential father, is still listed as a female on the World Wildlife Fund's master list of pandas of the Western world.

The London male, in other words, turned out to be a female and the London female turned out to be a male. The Chicago female turned out to be a male. Even our own male Hsing-Hsing is listed as female on the Western world list, and our female Ling-Ling is listed as a male.

If a laymay may be permitted to say so, a preliminary step in the breeding of pandas would seem to be ascertaining the sex of the animal before post-mortems. If all four of the London-Washington pandas have switched sex on us, one wonders if panda breeding in zoos really has a future.

Dr. John Knight, London vet who with other magi and spear carriers accompanied the regal Chia-Chia to Washington, said laboratory analysis has proved Chia-Chia not merely a possible sire, but a humdinger, as it were.

Without being gross about it, there is no question whether now about Chia-Chia's gender.

Yesterday our zoo's Helen (Ling-Ling) sat in a center room behind glass, while to the right (slurping his rice and cottage cheese) sulked the local Menelaus, the "inept" mate, as a zoo official once cruelly called him. But on the left bright Paris sparkled, swinging his bamboo canes like every flashy lover you ever saw. The lady, who could not see him but doubtless sensed his presence next door, dallied with some chopped carrots and rolled an apple with her paw. It was, in a way, positively disgusting, and more than one visitor made a point of going down to the cage of the old mate and hollering to him to just hold on -- this flash-in-the-pan from London is just another pretty beach boy and won't last. What a girl needs, and is quite lucky to find, is a steady mate through thick and thin, even if he's at some disadvantage compared to the newest yo-yo blowing in from London. Jabbering about the theater, no doubt, and what Prince Charles said last Thursday.

The Chinese, who name the pandas they give to selected Western zoos, have an apparently unstoppable fondness for Chi-Chi and Chia-Chia (London) or Hsing-Hsing and Ling-Ling (here). Possibilities for confusion might be less if sensible names like Philip and Penelope or even Philip-Philip and Penelope-Penelope were given. And yet one would not be rude, of course, since it is generous of the Chinese to let any pandas out of the country at all, since it is feared there may not be more than a thousand pandas now alive on the earth.

A trend has been spotted, in the literature of conservation, to call the panda "the most admired animal," somewhat like Walter Cronkite trustworthywise.

Meaningless, of course, and misleading. In any show of support, who doubts the tiger, elephant, leopard, lion, unicorn, whale, basset, black-nun pigeon and comet goldfish would head the list? And yet there is some point to it, this exaltation of the panda, since it is endangered almost beyond belief in its struggle to survive, and nobody can view its cuddly sweetness without a pang, for as our greatest wit once said, we love that well, that we must leave ere long, and (again) how can summer's honey breath hold out?

Pandas are very fond of honey, said Mike Morgan of the zoo staff, and they eat a relatively revolting mess of sloppy rice mixed with cottage cheese, honey and a dollop of horse meat.

The new dream weighs 246 pounds, and like all pandas his gigantic head is mostly bone and muscle, though he does not look like a jock, and he is strong. He can take a 12-foot-high culm of bamboo and cut through it with one quick sharp bite, though only a strong man could cut through it with one stroke of a machete. Those who have spent happy hours cutting bamboo are invariably astounded to see a panda cut through an old stalk as if it were a strand of spaghetti.

Dr. Brian Bertram, London's curator of mammals, was pleased to see Chia-Chia's great shipping case on display in the Panda House, a dazzling object enameled in glossy white and black with heavy locks, a work of art befitting the jewel who will return to London in it in June.

Pandas are carnivores who apparently have adapted to a fare-thee-well and who now live chiefly on bamboo, which has little food value (and of that little, pandas absorb only 50 percent) so that vast quantities must be processed daily. Dr. Knight said he thinks of pandas as great mowing machines.

Pere David, the notable French missionary in China, sent the first skin and skeleton to Paris in 1869 from Szechuan and named it Ursus melanoleucos, lumping it with the bears, but later the giant panda was assigned to the genus Ailuropoda (meaning cat-foot), referring not so much to its exquisite paws as to its remarkable wrist.

The panda folds its five fingers back against this wrist and thus holds its bamboo. But it's not that the panda simply has a long wrist. Its radial sesamoid (bone) spurs out from the wrist, and is controlled by two ingenious muscles, so that for all practical purposes the panda has five fingers and a thumb. This sesamoid cannot be used as an opposable thumb (we humans are endlessly proud of our own, of course, and a bit touchy about pandas having five fingers and a thumb of sorts) but it works admirably for its great purpose of holding bamboo culms as the panda works to strip off the leaves. That is something that related animals such as bears and raccoons cannot do.

Once the panda ranged widely down the coast of eastern China. Possibly in competition with other carnivores, it was obliged to move westward and to higher elevations (above 6,000 feet) where it has no enemies of consequence. Its home is the area of bamboo forests -- not at all like the great tropical bamboos of India, but hardy bamboos such as we grow in gardens here (and which came, of course, from China).

Observers have said that in the wild a panda may spend 10 or 12 hours a day eating, though this seems absurd on the face of it, yet it must be remembered that in the wild the panda must gain from bamboo alone all the nourishment that in zoos it gets from grain, fruit and meat.

Unfortunately, not much is really known about pandas in the wild. They are solitary animals, they roam about (as gorillas do) without a home cave or anything of that sort, sleeping when the flesh wearies and at the base of any tree they bump into.

The Chinese of panda country call them "white bears," and needless to say think the world of them. When a pair was shipped to Berlin, people at the Chinese zoo wept openly. (Their curator bore up fairly well until one of the pandas turned and seemed to be looking for his friends, just before the door shut on his crate, and then the fellow burst into tears). It was the same (as a Spanish ambassador reported at the time) when pandas were shipped to Madrid. You have only to think of shipping off a well-loved hound to some new home in some wilderness or other to comprehend the effect on the Chinese when their pandas leave.

Since 1937 only 30 pandas have gone to zoos outside China and of these only nine are alive now, according to the World Wildlife Fund list. In China, several pandas have been born in zoos and some have survived. Usually there are two at a birth, sometimes one and occasionally three. A panda was born alive at the Mexico City zoo, but did not survive (its mother sat on him).

The Chinese have a legend, that a sweet girl who lived at the Resting Dragon Mountain was of such gentle temperament that she came to love all the wild pandas she met and they in turn loved her. One day a leopard attacked a little panda and the girl defended the panda but was herself killed by the leopard.

At her funeral the weeping pandas wiped their eyes with their paws which had brushed against their mourning black. Hence the black around the eyes.

Then (the Chinese, by the way, have a great stock of panda stories) there was a panda who forgot he was supposed to be a solitary animal. He got rounded up with a flock of sheep, spent the night in the barn, had a breakfast of porridge and departed through the barn roof. Perhaps like his relative, the raccoon, the panda sometimes surprises people by doing the unexpected.

Pandas love globular things. A tractor driver was stopped once by a panda in the road. Waiting, he assumed the panda would get out of the way, since pandas do not like strangers much. But the panda walked up to the headlights and pawed the light bulbs for quite a while, oblivious to the driver.

Another panda got into a supply of clothes and food stored by some workmen. He was caught red-handed with a cooking pot lid, which evidently fascinated him and which he put on his head like a beret. He then rolled it down the hill and trotted after it into a bamboo grove.

Best of all, maybe, there was a panda in Szechuan who strolled out of the bamboo to where a celebrated painter was at work on a landscape. The man threw a couple of brushes, but the panda paid no attention and walked right up to the canvas. The painter retreated. The panda then picked up the canvas, studied it for several minutes and tossed it into a clump of bamboo before waddling off.

The National Zoo is the only place outside China iteslf in which you can see three pandas. There is a pair in Mexico, but only two in America, until Chia-Chia arrived on detached duty.

The Chinese have already spent millions on pandas, establishing preserves for them, to a total of 30,000 square kilometers.

Pressures of human society and human expansion have done most to limit the panda population in the wild, but there are other hazards that cannot be blamed on us.

Different bamboos flower and die at different intervals, but when they do flower, virtually all that particular species flower at the same time. Even when bamboos are grown in the West, a certain bamboo will flower and die in Algiers, Brooklyn, San Francisco, London and Paris, often in the same year. So it is not much exaggeration to say the same bamboo will die, worldwide, according to its natural (and not at all well understood) cycle.

In the wilds of western China one species of bamboo died in 1975 and 1976, and that was the only species available to the pandas. It is feared that 100 pandas will starve to death.

The World Wildlife Fund years ago adopted the panda as its own trademark or logo, a symbol of the effort to keep life alive. World Wildlife Fund and the Smithsonian Institution-National Zoo have joined in a panda project to raise a million dollars (against the total of $4.5 million needed by the Peoples Republic of China in its panda conservation program). Already Dr. George B. Schaller (winner of WWF's gold medal in 1980 for his conservation work, and member of the New York Zoological Society staff) is in China. A research center is being established there to learn more of the panda's ways in the wild -- a fairly spartan center.

"There is now a great dying," he said in an address last year, "as mankind reduces the earth's natural complexity. Often the decline is slow, insidious. rThe gorillas I studied 20 years ago have been reduced by half; valleys where I met the snow leopard 10 years ago no longer feel the soft tread of the cat . . ."

Nobody wants to see the day in which the bamboo groves no longer resound to the chomp-chomp of the bear of bears.