By definition the dog days are those late-summer days especially characterized by sultry weather. So they were for the Westchester Kennel Club's 42nd Annual Dog Show at Purchase, N.Y., which fell on a day of steamy sunlight and listless air. But the occasion was the height of the dog days in another sense. The choice of best-in-show in this year's Westchester was literally a show-stopper. Somehow the word spread through the crowd of 7,800 that this would be Donner's day. Donner is Storm's Donner, a 3½-year-old Doberman owned by Peter Mehlich, a Manhattan artist. Shown 32 times, Donner had won many a best-of-breed and seven best-of-group but never a best-in-show.

Extra interest arose because of his ancestry, for Donner is the product of what fanciers call "close-line breeding"; the son of the legendary Rancho Dobe's Storm and of Storm's own daughter, Storm's Tempesta. Storm p√®re earned his legend by winning the highest American dog-show honor twice—best-in-show in the Westminster in 1952 and 1953. (Storm was never entered in the Westchester, since his owner, Len Carey, was a Westchester official.) Close-line breeding is considered risky in that it may result in an overstress of weaker qualities. But Donner, dark, sleek and lithe, turned out to be an uncanny replica of his distinguished parent.

Brilliantly handled at the Westchester by Peter Knoop, a Wall Street investment banker with a clairvoyant understanding of canine moods,: Donner was everything a champion should be: alert, responsible, good-natured and vibrant, and with an air of enjoying himself instead of an air of tension. When Donner was chosen best of the 1,664 dogs in the Westchester the crowd roared its approval.

PHOTOHANS KNOPFMASTERFUL HANDLING by his owner Dr. Edward Vardon and his own admirable bearing brought bulldog Vardona Frosty Snowman victory in nonsporting breeds.
PHOTOHANS KNOPFIMPECCABLE POISE and air of serene wisdom made smooth dachshund Celloyd Daniel, winner of the hound group, another crowd favorite at the Westchester show. PHOTOHANS KNOPFCRISP PERFORMANCE of Mr. and Mrs. William Rockefeller's Bedlington, Draherin Blue Andante, a runner-up last year, again won him first in the terrier group. PHOTOHANS KNOPFVIBRANT RESPONSIVENESS OF CLOSE-BRED STORM'S DONNER, BEST-IN-SHOW, WAS BROUGHT OUT BY HANDLER PETER KNOOP PHOTOHANS KNOPFLORDLY LOOK is worn by sporting group's best, English setter Zamitz Jumpin' Jack. PHOTOHANS KNOPFCONFIDENT APLOMB of toy poodle Nibroc Gary, owned by Mrs. Peter Frelinghuysen of Morristown, N.J., marked his victory in toy group over field of 242 rivals.