For a few moments today, the Baltimore Colts pretended they belonged in the National Football League. Then the Dallas Cowboys kicked off, and soon 54,871 at Memorial Stadium saw why their team is unfit for family viewing.

The Cowboys intercepted David Humm on the first play from scrimmage and scored on their first five possessions in routing the listless Colts, 37-13, and taking a two-game lead over Philadelphia in the NFC East Division. The Cowboys play the Eagles Sunday in Dallas.

It was Baltimore's 13th straight loss, seven by 22 points or more. The Colts play the Redskins next Sunday in RFK Stadium.

Even with injured quarterback Danny White only watching, the Cowboys methodically kicked the Colts. Tony Dorsett rushed for 175 yards on a personal high 30 carries and Ron Springs scored three touchdowns in a game quietly settled by halftime. The Cowboys gained 464 yards.

In the proud new Baltimore, someone forgot to refurbish the Colts. Baltimore's Best have given up the most points, first downs and yards of any NFL team. From the muffed opening kickoff to an interception on their last offensive play, the Colts looked to be in a state of disarray.

"It's sad. I felt sorry for them," said Cowboy defensive tackle John Dutton, a former Colt. "They're not bad athletes, it's just a bad situation where they are. It's hard to work for an organization that doesn't care about you. That's the way it was when I was here, and I know the feeling."

"I've been through it in New Orleans," said defensive tackle Mike Fultz. "Little things go wrong around here and really snowball."

Baltimore quarterback Bert Jones, hobbled by a variety of injuries, did not play, and Coach Mike McCormack said he wouldn't have played under any circumstances. Humm, a seven-year pro out of Nebraska signed a week and a half ago, quickly discovered the pain of being a Colt. He also discovered real pain on his team's final offensive play, when the middle finger on his throwing hand was dislocated.

On Humm's first pass of 1981, defensive end Ed Jones tipped the ball and linebacker Bob Breunig made the interception at the Colt 17. Four plays later, Springs scored from the one and the Cowboys had a 7-0 lead with 1:45 gone.

"If all of the Colts' psychological problems we hear about are true, then that first play blew them worse," said Cowboy safety Charlie Waters. "It was a big play. It put them down and maybe out immediately."

After the Cowboys' lead grew to 17-0, the Colts finally responded on a 67-yard touchdown run by Curtis Dickey, who gained 130 yards rushing. With 1:04 left in the first quarter, it was 17-6, because Mike Wood missed the extra point.

When the Cowboys got the ball back, they stunned the Colts with a 59-yard flea-flicker from Drew Pearson to Tony Hill on their first play. That set up Glenn Carano's two-yard scoring pass to Springs on the first play of the second quarter and a 24-6 margin.

The Colts, perhaps Baltimore's next urban renewal project, went into halftime behind 27-6. Humm completed one of 11 passes in the half, and the Colts had three first downs to Dallas' 16.

Because of the 24 mile an hour wind and with White out, the Cowboys ran. Carano, seven of 18, 51 yards, proved competent if unspectacular in his first start this season.

The only inspiration of the second half came from White. Apparently bored at being restricted to punting, he ignored his sore ribs and took off down the left sideline on fourth and 10 midway through the final quarter. He ran out of bounds, unscathed, with a first down at the Colt 38.

"I could have shot him," said Cowboy Coach Tom Landry.