SOME swell institution it must be that throws together bang-up productions of Anything Goes, Gypsy and Pajama Game all in a season. Harvard can boast one of the niftiest informal musical comedy ensembles around. For the truth of the matter is, while they incline to shuffle their names and titles around a bit, the same little pikers in back of those other two shows--let alone much of the more resounding Cambridge entertainments over the last three years--are responsible for the latest and in lots of ways the most dazzling of them. People like Stu Beck, Bob Bush, Shannon Scarry, Bea Paipert and Josh Rubins have become integral parts of the local scence--like parking meters and potholes.

For posterity, it could be mentioned that Mr. Beck, one of the solider citizens of the clan, is leading the way these evenings at Agassiz. His decision to turn director encounters none of the flak that has struck dead certain other undergraduate actors with that bent. Instead he demonstrates an honest to God flair for it and you frequently notice his nimble fingers fudging nimbly over some intrinsic flaw among the raw materials. Performers who might otherwise not belong on stage make good on Mr. Beck's stage, and that's no mean tribute.

Lest anyone question where acting ends and directing begins, and how such distinctions can be made by an outsider, (and, mind you, I've nothing to do with this show though you won't believe it after reading this review), be it ventured that one can make a fine estimate of a director's involvement when the show is as consistent and tasteful as Mr. Beck's Pajama Game. Either he's first-rate or my mother's name isn't Velvetina.

BUT like the saying goes, you can't paint the painting without the paint. Director Beck has himself a little whale of a cast, fully equal to the show and with voice enough to fill the theatre and then some. Not a song gets roughed up more than momentarily. And the bulk of them, emphatically "I'll Never Be Jealous Again," "Small Talk," "Hernando's Hideaway" and "Seven and a Half Cents," hit it big.

The cast is a shade too adequate on the whole to be worth singling out more than perfunctorily. Bob Bush acts and sings, mostly sings, the part of Sid with more ease than one has right to demand in a community not known for its male leads, particularly of the musical variety. Josh Rubins gets the requisite number of laughs as Hines. And Bea Paiper, Pren Claflin, Chris Arnold and Shannon Scarry are supporting players who actually lend support. Miss Scarry, bigger than life, lends some-what more support than the rest.

If anyone hasn't heard of The Pajama Game--like he's been simmering in a bubble bath since Douglas MacArthur flew home--it should be noted that, by virtue of its terribly attractive songs and its breathtakingly blemishless book, the show ranks rather high in its chosen category. For reasons already labored, and because of a virtuoso turn on the part of Peter Larson, who came late to the job of providing an orchestra, the production ranks almost equally high.