E ven i n g DRAMA • BY BARBARA PASH urn up the heat with this fall's favorite cocktail dresses. Lean and leggy short lace dresses, body- hugging sequined numbers, and the ever-popular little black dress, now with low-low necklines and open back treatments, bring fashion excitement to the start of the social season. Wornen's Wear Daily, the bible of the fashion industry, reports that spe- cial-occasion designers are drawing inspiration from two quite different eras for this fall's dressy apparel. In case you hadn't noticed, the 60s are back — parts of it, anyhow. One part that designers have latched onto is A.J. Bari eveningwear division was expecting a 25 percent increase. Julie Duroche, of Julie Duroche for After Five, told WWD she is doing two styles: evening separates in velvet, wool crepe and rayon crepe with brocade jackets; short, low-cut black Lycra spandex dresses, her "Holly- wood" look. For the Leslie Fay Evening division, designer Jimmy Dougherty is concen- trating on baroque-inspired styles including the "double dress" that combines a damask linen top with a matching-colored polyester chiffon skirt. Morris Marmalstein, president of fringed-bottom velvet jacket," she was quoted in WWD. Still, she added, her best seller for fall so far is a sexy, black off-the-shoulder "Marilyn Mon- roe" dress. At Lord & Taylor, vice president of fashion merchandising Lavelle Olexa said the "bare body" little black dress was selling well for fall but an orange taffeta short dress was also attracting buyer interest. Cocktail dressing can be divided into two major looks this season. One look is the short, body-concious dress — very sexy and bare in gold lame, beaded, and fringe trim. The second look is very dressy, very opulent with Evening fashions sizzle with opulent textures and sexy styles. the short, curvy black dinner dress, resurrected in Lycra blends and other stretch fabrics that didn't exist 30 years ago. The second era is even further back — we're talking the Renaissance — and opulently orna- mented "baroque"-looking dresses and suits. Designers, manufacturers and retail- ers gave their opinions on the season ahead which, not surprisingly and in a nutshell, they thought would be splendid. Jon Levy, president of the St. Gillian Group, reported that the 70 STYLE David Warren Enterprises, which has three eveningwear divisions, said that "black is still 90 percent of the collections, but we went out of our way to do colors and prints for fall." At Susan By Night, a company that debuted last spring with an all-black line of dresses in polyester and Lycra knit, owner and designer Susan Lunenfeld said she is adding red, blue and deep purple for fall. "The look is simply hot and heavy. I'm showing more Chanel-inspired jackets with multicolor rhinestones, as well as a brocade and panne velvet. The textured fabrics are usually associated with ball gowns and are being used for cocktail dresses. Local stores report that fitted dresses with Lycra blends are on the racks. In addition to the strapless gowns, the illusion neckline with a see-through netting is popular. Also, watch for simple tank dresses. There are many alternatives for women who cannot wear slinky dresses or do not feel comfortable in the fitted styles. Two pieces dressing