Until Peter Gabriel happened on the scene perhaps the eeriestthing around was Vincent Price in all manner of gruesome guises in filmadaptations of Edgar Alan Poe horror stories. Then the Genesis singer putan end to all that with an act that is at best intriguing and at worst spinetingling.

 Gabriel has his own tame mask maker who turns out such delightsas bat wings, fox's heads, illuminated geometrical hats, flowers, old men'smoosh's and God knows how many other creations.

 As if this is not enough, Peter has perfected the knack ofappearing on a darkened stage with his eyes gleaming from the blacknesslike Christopher Lee with a bad attack of the late-night blood lust. Theatricsplay a large part in Genesis' music and it's all preconceived.

 While admitting that his partially shaved head is a gimmick;Peter says: ''The difference between us and other bands who are into theatricsis that when we've recorded a song we decide how best to present it onstage rather than just put on costumes which bear no particular relationto the music.''

 Genesis are working on the idea of using cartoons to furtherenhance their act and in the meantime have devised a whole new performancewhich has recently been unleashed on the Americans.

 "We are trying to create images and moods with the music andwe want to use any tools at our disposal to enhance the music. We neverwant the visual aids to dominate the music and I don't feel it ever getsto that stage with us as it does with certain other cases. I would liketo see our stage act as being strange in an introverted fashion ratherthan an extroverted fashion and I don't think that's a contradiction interms.

 ''As long as what I'm doing is coming from what I feel ratherthan routine or contrived effect then I'm quite happy that it's justified.''

 Another idea the band has in mind is that of using a portabletheatre where the audience would be involved in a fantasy during the two/threehour show, not only from the stage but via things going on around them.

 ''We work under a fantasy and my part has been to conceiveall the characters and masks I can from a piece,'' Peter points out. ''Thevisuals are really just an adaptation of something that's already beenwritten. They began out of necessity; with gaps in the playing the doorwas left wide open to me. Visuals can only succeed if the music is justas satisfying, it's actually a means to an end.

 ''Visuals should provide some images that sink into the music,so if you're listening at home you've still got traces of the charactersfloating around inside your head.''

 Genesis' rise to stardom had not been instant. Those who thinkof an overnight success story are quite mistaken. The band was formed atCharterhouse, where all the original members were educated, in 1966. Theymade a rough demo tape which met with customary disdain from the majorityof the music business until whizz kid Jonathan King took an interest inthe group and spent the princely sum of £10 financing another demorecording session.

 Decca issued three singles and an album between 1967-68 butnone of them did a lot of business and the group soon found itself in debt.Peter Gabriel had this thing about becoming a drummer rather than a singerand what with one thing and another the band was on the verge of splittingup several times.

 ''But I had this confidence that if we stayed together we wouldachieve success,'' he now recalls.

 Then Rare Bird heard Genesis and recommended them to Tony StrattonSmith who signed them and appointed John Anthony their record producer,job that is now filled by John Burns and the group themselves.

 Of those early days when things weren't too happy, keyboardman Tony Banks says: ''Jonathan King was real quite kind and he liked oursongs and didn't try to influence us. I don't think we'd really sortedout a direction at the time though and we were still rash, amateurish inthe studio.''

 As time elapsed, the-songwriting tale' of Genesis became moremature an now in these days of the ''Selling England By The Pound'' albumthe writers are recognized as being among the most promising of the currentcrop

 ''People place all kinds of interpretations an our songs butI think that healthy, it shows some kind of thinking a contribution ontheir part,'' Tony considers.

 Genesis started life as Peter Gabriel, Tony Banks, bassistMike Rutherford and guitarist Anthony Phillips. Drummer, Chris Stewartjoined later only to leave after a year or so and be replaced t John Silverwho was in turn later succeeded by John Mayhew in 1969. The following yearPhillips and Mayhew left and Phil Collins joined on percussion and drums.The latest recruit was lead guitarist Steve Hackett in 1971.

 One music paper recently describe Genesis as ''Definitive gram-rock''but would argue with this description. It applies glitter and tinsel andpoovey make-up, none of which is evident in Genesis' act. Their embellishmentshave a purpose rather than being purely for decoration and the music hasclose affinity with the supernatural than with rock.

 A year ago I tipped Genesis for stardom after hearing the bandand its albums and listening to Phil Collins talk about the plans for thefuture. Genesis have made it and what is more satisfying, made it on thestrength of the music and related actions.