About thirty years ago a cowboy took me out to see “The big Dog-town.” This metropolis was in the heart of the great plains near the Kansas-Colorado line. For five hours we rode westward along the southern limits of the town. It extended on over the horizon more than two miles wide and about forty miles long. A town with a population of two million! Its visible inhabitants would have astounded a census-taker or a dog-catcher. Thousands of prairie dogs were yipping and barking more than sixty times a minute, and stub tails were whizzing away at the same time. We rode out among the crowded and protesting dogs and stopped to watch them. A number ducked into their holes. Around each hole was an earthy collar less than two feet across and four or five inches high. At a distance this earthy collar surrounding the hole had the appearance of a low mound. Evidently this mound is to keep out storm water. There were thousands of these holes, each with its dog. One near-by dog sat up on his mound like a ten-pound sea lion. He watched us with concentrated attention. His tongue and tail were still. When my hat started toward him he simply dropped into the hole. There were scattered holes which had a rabbit or two little owls at its doorway. Throughout the town were little orchards of dwarfed sagebrush and a scattering of tall weeds. A showy bed of prickly pear cactus inside the town limits was not inhabited. The prairie dog is a sun worshipper. He keeps aloof from localities where willows are an enemy-hiding screen and where trees cast a shadow. His populous cities are in arid lands where for three hundred days each year they have their place in the sun. The dogs seemed to be ever moving about, visiting or barking. A young dog near me ambled over to visit another. These two called on a third and while in session were joined by one’s, two’s, and companies until there were several dozen massed. A young dog left his hole-top after a survey and started off for a call. But he turned aside to join and mingle with the crowd for a minute or two, then went on with his call. All this time there were several dogs behind me energetically protesting at or about something. Cheerfulness and vivacity characterized this fat, numerous people, but they were always alert, and commonly maintained sentinels scattered throughout the town. While numbers were visiting or playing a few were feeding. They appeared to feed at all times of the day. But I do not believe that they eat half the food of the average woodchuck. The short grass was the principal food. They also ate of the various weeds around. I do not recall seeing them eat the bark of sagebrush or any part of the prickly pear. Prairie dogs must materially assist in soil formation. Their digging and tunnelling lets dissolving water and disintegrating air into the earth and deepens the prairie soil.