One of the most fascinating places to observe both chipmunks and these ground squirrels is from the windows of the long tunnel leading northward out of Zion National Park. On the talus slopes beneath the windows a great number of these rodents take up summer quarters, depending for food on the largesse distributed by visitors as they eat their picnic lunches on the broad ledges of the windows. Their constant movements as they run among the rocks seeking stray crumbs result in many a collision and often an angry dispute as well. This proves a dangerous game, as rocks sometimes will be loosened by their movements and roll down the steep incline. I recall seeing a ground squirrel crushed by one of these miniature rock slides in 1946. White-tailed prairie dog _Cynomys gunnisoni_ (Greek: kun, a dog and mys, mouse ... for Captain Gunnison whose expedition took the type) [Illustration: white-tailed prairie dog] Range: Western Colorado and eastern Utah to central Arizona and New Mexico. [Illustration: Habitat map] Habitat: Grassy meadows and mountain parks mainly in the Transition Life Zone although they are often found both above and below this area. Description: A ground-dwelling rodent somewhat resembling a ground squirrel but several times larger than the biggest species of that genus. Total length 12½ to 15 inches. Tail 2¼ to 2½ inches. Weight 1½ to 2½ pounds. Color buff to cinnamon buff, the short fully-haired tail tipped with white. Sides of face darker with a dark area over the eyes. Legs, feet, and underparts pale cinnamon buff. Young, usually five in number, born in early summer. _Cynomys gunnisoni_ is the representative species of the western group of prairie dogs. The two remaining of the group, _Cynomys leucurus_ and _Cynomys parvidens_, both white-tailed species, are very similar and possibly will be classified with _Cynomys gunnisoni_ in the future. _Cynomys leucurus_ is found in northwestern Colorado and northeastern Utah, while _Cynomys parvidens_ is native to mountainous valleys in central Utah.