Skyrocketing auction prices for first-rate modern pictures stopped skyrocketing last night.

Paintings by such masters as Renoir, Piscasso and Magritte failed to find buyers at Christie's in Manhattan. Although $10.4 million worth of modern art was sold in the evening's sale, grim-faced auctioneers had optimistically expected a total take of $15 to $21 million. Not since 1974 has the market shuddered so.

A splendid portrait by Edgar Degas of Eugene Manet, the painter's younger brother, did fetch the handsome price of $2.2 million, more than doubling the previous auction record for Degas. But there were few other high points in the gloomy sale.

Degas did the portrait as a wedding present for the painter Berthe Morisot and the young Manet in 1874. It was clearly the most impressive picture offered in the sale.

Not far behind was a sunlit van Goh streetscape of 1888, which sold for $2.1 million. The van Gogh price was not even half of the van Gogh record of $5.2 million set by a larger though not more beautiful landscape last year.

The bidding was lethargic, the well dressed crowd subdued. Time and time again, the paintings on the block did not even reach the low end of their pre-sale estimates. The sale began poorly and gradually got worse.

It opened with a group of "Eight Important Paintings" from a mystery collector." Only three -- the van Gogh, a $1.3 million Gauguin still life, painted during his last visit to Tahiti, and the Degas -- sold.

The other five, among them a Renoir portrait, a Monet seascape, a famous Cezanne canvas of an abandoned house and a small van Gogh of hungry rats nibbling at a crust of bread, an allegorical Morisot based on a Boucher, fetched less than had been hoped and were bought back by the "mystery collector," a man variously indentified as an Italian, a Bostonian or, most frequently, as Demitry Jodidio, whose family publishes Conaissance des Arts, the French magazine.

The second section of the auction also was a bust. Offered was "The Enchanted Domain," a cylce of eight mysterious canvases by Rene Magritte, the late Belgian surrealist.

The oils, painted in 1953 for a mural project for the gambling casino at Knokke on the Belgian coast, reiterate the painter's most familiar theme -- the flaming tuba, the man whose body is a birdcage, the leaves that are also birds and the nighttime street seen below a daytime sky -- were expected to sell for a much as $2 million. They didn't. Bidding stopped at $1.7 million and because the whole lot did not meet the minimum prices set by their seller, remained unsold.

The third section of the sale was comparably disappointing. Of the nearly 50 pictures offered, only half dozen did better than expected. Many did much worse. The painting. "The Dream," a 1931 canvas by Salvador Dali, was expected to fetch more than $400,000, but bidding stopped at $280,000.

The cubist Picasso reproduced on the cover of the catalog had been expected to sell for about $1 million, but, perhaps because it had been damaged and restored, bidding stopped at $700,000 and the painting remained unsold.

Fifty-eight lots were offered at last night's sales. Twenty-two remained unsold. The results of a sale of German Expressionist paintings held during the afternoon were even worse. So many German pictures failed to find buyers that only a third of the $1.35 million bid was actually collected.

The rising value of the dollar, the sinking value of the pound, the franc, the yen, and the high interest rates prevailing were all blamed for these results.

"The yen is down," said David Bathhurst, Chirstie's president, "and there were no Japanese to speak of here. Prices have been going up very steeply in recent years. That can't go on forever. With interest rates what they are, dealers have to be super rich to buy million-dollar paintings for stock. I'm not sad to see an evening out of prices. Compared to the 1974 shakeout, this is a hiccup -- not a slide."

The week-long spring carnival of art auctions began inauspiciously Monday night when Christie's offered the private collection of Saul P. Steinberg, the New York financier. Steinberg, chairman of the Reliance Group, is selling his $10.6 million, 20,000 square-foot, 34-room Park Avenue duplex and his pictures, too. Christie's had estimated they would bring a total of $7.5 to $9.5 million. They didn't. The actual take was $4.52 million. Less than two-thirds sold.

Christopher Burge, Christie's director of fine arts, watched the sale from his wheelchair. His right foot was broken Wednesday, when he fell while installing one of the Steinberg paintings. "You figure the prices came tumbling after?" one reporter asked him. Burge did not smile.

The auction will move to Christie's New York competitor, Sotheby Parke Bernet, tonight, where 73 objects from the Chicago collection of Mr. and Mrs. Leigh B. Block will be offered. CAPTION: Picture, Detail from Degas' painting which brought $2.2 million.