Devora Grice, age 10, of Imperial Beach, California, for her question:

Which is the biggest breed of dog?

This depends upon whether you measure a dog by his height or his bulk, which gives his weight. It so happens that the tallest dog is not the bulkiest, or the heaviest. Dog experts tell us that there are about 116 different breeds of the domestic dog. And the tallest is the long legged, long bodied Irish wolfhound. Standing on all four feet, his shaggy shoulders are three feet above the ground. When he stands up on his hind legs, he can reach to a height of at least seven feet.

No other dog can match these measurements. But other breeds have chunkier bodies. They are bulkier and heavier than the elegant Irish wolfhound. One of these is the sturdy Saint Bernard. He stands less than three feet at shoulder level and his body is shorter than the champ's. A huge mastiff may be as big and bulky as a Saint Bernard. Either of these dogs may weigh up to 180 pounds which is heavier than the wolfhound.