Appearing on French television following Sunday's election, Communist leader George Marchais' joyousness was in sharp contrast to the funeral expressions on the faces of his Socialist allies.

The Socialist leaders were taking the defeat of the Left like a death in the family. Marchais, however, acted as if he had just won top prize in the national lottery.

In a sense, he had. Even though the Communist Party emerged from the elections as the smallest of the four major political groups on the French scene, it succeeded in winning more of its immediate objectives than any of the others.

They were not the objectives to which the party admitted publicly, but Communist tactics made clear what they were.

A large number of independent analysts, including leftists, agree that the Communist Party's pursuit of its own parochial interests over those of the united left is the basic explanation for the center-left electorate's last-minute desertion of the leftist coalition.

Nevertheless, the Communists managed to:

Maintain their electoral strength of about a fifth of the voters in the face of separate vows by Socialist leader Francois Mitterrand and President Valery Giscard d'Estaing to reduce them first to 15 per cent and eventually to an almost marginal 10 per cent.

Preserve French communism's acquired position as a parallel society within its own companies, banks, municipalities, schools, summer camps and holidays.Ideology is not the only thing that makes the party like a church. It has all the other trappings - bazaars, collection plates and social clubs.

Cut down to size the French Socialist Party, which was threatening to run away with the leadership of the left by becoming its dominant electoral force. In defeat, the communists maintained their hold on half of the left.

Preserve its long-term option of a "historic compromise" with the Gaulist party as the ultimate road to power along the lines now being followed by the Italian communists.

This long-term strategy involves reinforcing the French Communist Party's mutual interests with the Gaullists in squeezing out the center of the French political spectrum now occupied by the Giscardists onthe center right and the Socialists on the center left.

Communist voters were occasionally confused by the frequent tactical zig-zags by Marchais during the campaign, but there was no party rebellion against them. There were not even any of the punlic expressions of doubt that such brusque changes in party line would almost surely have elicited in any other political organisation.

As a result, the image of the French Communists as liberals in the Euro-communist mold has been darkened in France - perhaps for good - and most of all inside the noncommunist left.

No more severe judgment has been passed on Communist behavior than the socialist party Executive Bureau's declartion Monday night that the disunity of the left was "deliberately provoked by the leadership of the Communist Party, which had no other concern than to try to reduce the advance of the Socialist Party, even though that was one of the necessary conditions for common victory."

"By multiplying his attacks against the Socialists," the Socialist declaration continued, "Georges Marchais helped the right and postponed the hour of change. It is for the workers to draw the proper lesson from that behavior."

The Communist answers to such criticism put the accent on the party's success in thwarting attempts of the "bourgeoisie" to weaken the party and push it into decline.

A Political Bureau statement notes that while the Communist Party lost seven-tenths of a percent in its share of the vote compared with the legislative election of 1973, the Communists actually gained 700,000 in the popular votes and picked up 13 more National Assembly seats.

The smallest member of the leftist coalition, the Radicals of the Left, seem to be on the verge of a schism over joining forces with Giscard. Socialists have called for Mitterrand's resignation as party leader, and the Socialist Party's strong left wing voted against the Executive Bureau's attack on the Communists. By contrast, Marhais seems, ifanything, more secure than ever.

The French Communist Party enjoys tactical independence from Moscow. When the Kremlin stripped celist Mstislav Rostropovich of his Soviet citizenship last week, the French Communist organ L'Humanite said it was "stupefied and saddened."

But the French party still has very close financial links with the Soviets. French Communists and Soviet Fianances are closely interwoven through party control of the bulk of France's share in East-West trade, most of which is handled by the Soviet bank in Paris, the Commercial Bank for Northern Europe.

While the Soviets have engaged in lively polemics against Spanish COmmunist leader Santiago Carrillo, widely regarded as the inventor of Eurocommunism, they are carefully neutral in their statements about the French party. Soviet diplomats in Paris call the French party line "an interesting experiment."

The French Communist Party has also dropped a great deal of the kind of puritanism that hurt its recuriting among the workers, whom the party itself admits make up only 40 percent of its membership. A new party pamphlet designed for distribution among non-communists quotes an anonymous worker as saying he does not want to have a life like his neighbor, who must work 12 hours a day to make ends meet.

"When he gets home, he doesn't even have the strength to make love to his wife. That's no life," the worker said.

It is increasingly clear, however, that if Eurocommunism means free internal party discussion of the party line, the French party cannot be called Eurocommunist.

The standard party phrase, from top to bottom, to get approval of a decision presented by the leadership is "any contrary oponions?" Those who have participated in such meetings say that there almost never are.

Nothing resembling open discussion goes on in the higher reaches of the party, although it is said to be somewhat tolerated in local cells because the party is realistic enough to know that it cannot control the tongue of ordinary workers, students and teachers - who represent a disproportionate share of the membership.

It is very hard, however, for currents of opinion from the rank and file of the party, which is organized pyramidically from the top to the cells at the base, to be transformed into factions that could challenge the line followed by the leadership.

Organization of such internal dissent is strictly illegal and is grounds for expulsion. Party organizations may communicate up toward the top and down to groups under them, but they may not talk to each other laterally across the face of pyramid.

Known as democratic centralis, that is the basic organizational principle that distinguishes a Communist Party from a Socialist one. The French Socialist Party gives official recognition to factions; the French Communists are as strict as any other Communist Party in the enforcement of their military style organization.

Mitterrand's strategy was based on the assumption that he could bend the Communist Party machinery to his will, and maneuver it into helping him to power and doing his bidding afterward.

France's Communierward.

France's Communist Party, however, had the strength and the sheer political will to upset all his calculations.