Thin Is In : Menswear for fall means skinny ties, pants, jackets. Oh, and mohair. And dickeys. Really.

The shape of things to come? For fall, it’s narrow, as New York menswear designers serve up male waifs with suede-head haircuts in lean jackets, skinny pants and narrow ties.

Oh, but there was more to this week’s fashion shows. Military surplus styling. Space-age silver. Side-striped trousers. V-necked sweaters. Long-john leggings. Lean, long coats. Fuzzy mohair. And, the triumphant return of the dickey. Honest.

Here’s the skinny.

John Bartlett: When this fast-rising designer took a curtain call after his “Depression Modern” show Monday, some were calling him the future of American menswear. Could be. Big droopy “L’il Rascal” sweaters; elongated “salvation” coats in splotchy, Rorschach-like patterns; black apron-tie-wrapped waistcoats over bibbed shirts and side-striped trousers, and velvet jeans the color of vintage denim. These are cutting-edge clothes that never look silly. He even made the dickey look great--chunky, ribbed and worn over the shirt instead of under. Really.

DKNY/Donna Karan New York: Just back from Florence--where she was the first American designer to show at the influential Italian trade show Pitti Imagine Uomo--Karan put on a slick and exciting presentation with plenty of cool clothes to back up all the multimedia theatrics. Lean suits with slim jackets, skinny trousers, tab-collared shirts and narrow neckties were the newest wave in the DKNY line. Smashing too were silver down jackets and fireman coats, rubber-coated jeans and military-style jackets, and side-striped leggings. Best from her signature collection were suits with nearly ankle-length jackets, rubber-front jersey knits worn as tight as a second skin, and platinum-colored robe coats, cabled turtlenecks and sweat pants--all in Karan’s favorite cashmere.

Calvin Klein: V-neck sweaters; texture-rific three-piece suits; flat-front pants; fuzzy-side-out reversed shearlings; long, slim “cigarette” coats, and nary a gimmick as Klein embraced “the enigmatic period of time when Paul Bowles and Jean Cocteau created their most powerful work.” The best suits in this tasteful, luxurious collection were three- or four-button models in earth-tone ribbed crepe, gray crepe ottoman or ash-brown striped wool. Cashmere three-button sport coats were plush-toy soft. Tunic-style sweaters--a trendy V-neck preferably--often replaced shirts.

Tommy Hilfiger: Hilfiger embraced several of the season’s key trends--most notably the slim silhouette and military surplus styling. To pleasant effect, he turned out slim plaid pants, velvet and velvet-trimmed jackets (some three-quarter length), cargo-pocket fatigues, and navy peacoats with gray blanket stripes at the bottom.

Perry Ellis: Now designed by Richard Haines, the America and Collection lines scored points with military style, back-belted overcoats topping ribbed sweaters and cargo pants, and leather peacoats worn with ribbed sweaters and jeans.

Jhane Barnes: Barnes’ appeal is lost on me, but who can argue with success? Her best looks were oversized cardigans called “frock smocks,” worn over hand-painted waffle-weave long johns; a gray and oatmeal “baby boucle” sweater jacket worn with sage wool pants, and three- or four-button moire-weave suits with drapey pants.

Boing!: Ari Fruchter and Joe Soto called their latest Boing! show “The Return of Genghis Khan,” but there were a few dashes of Chaka Khan in there, too. Their mohair Henley top--one of the season’s most winning and offbeat ideas--hit the mohair trend in a rugged, inspired way. Other appealing looks included brown boucle mock turtlenecks, wide gray judo pants and faux Persian lamb-trimmed “Khan” jackets (three-quarter length, drawstring waist).

J.O.E./Joseph Abboud: Brown hooded cable sweaters, side-laced black-leather pullover vests, and band-collared jackets from the J.O.E. line were nice enough. Rust-colored cropped shearling jackets, slim Chesterfield coats, paisley vests under plaid jackets, and black Donegal double-breasted suits highlighted Abboud’s signature collection. But the formal-wear finale of men in brocade vests, no shirts and velvet pants (which looked more like night clothes than evening trousers) went right past tired into nightmare territory.