Harvard's unbeaten cross country team will be gunning for its sixth consecutive Big Three Championship when it lines up against Princeton and Yale at Princeton this afternoon.

The Crimson harriers have won nine races in a row this season and 21 straight dual meets over a three-year span. Coach Bill McCurdy feels his squad should have little trouble adding its traditional rivals to the string.

Princeton and Yale, however, have outstanding records this season. The Tigers sport a 7-1 mark, while the Elis match five victories against a single loss. By coincidence, both teams owe their defeats to single-point decisions against Penn, a team soundly thrashed by the Crimson, 16-47, early in the season.

Yale Star

In captain Frank Shorter, Yale has a proven runner of exceptional ability. Second to Crimson captain Doug Hardin in last year's Heptagonal meet, Shorter has won all six Eli races this season. He is respected by Harvard runners as a tough competitor, but has a history of being edged out in the big races.

Steve Bittner and Bob Yahn form a solid backup duet behind Shorter. Bittner, a versatile runner who can compete ably at any distance from the dash to five miles, has a strong finish any time he is within range of an opponent. The dimunitive Yahn has had injury troubles off and on, but has recently become a consistent top-level performer.

Yale lacks solid strength behind its leading trio. Seniors Carl Pierce and Steve Boyer have a chance for scoring positions today, but unless they can close the gap between themselves and Yahn, the Elis will be in trouble.

Unbeaten Tiger

Princeton's ace is junior Eamon Downey, who matches undefeated records with Shorter and Harvard's Royce Shaw. Tigers Rich Stafford, Tom Yunck, and Dennis O'Brien provide some backup, but time gaps of a minute or more between places in Princeton's top five have been common this year.

In contrast, the Crimson harriers boast seven runners who can all finish within a minute of the leader. This pattern has held even when the leader has set a record-breaking pace, as happened against Dartmouth a week ago.

Sophomore Dave Pottetti, fresh from Tuesday's Greater Boston victory, and steadily improving Keith Colburn can be expected to join Shaw and Hardin in a battle against Shorter and Downey for individual laurels this afternoon. Behind them Tom Spengler, Tim McLoone, and John Enscoe are good bets to outrun rival backup men.