However, though the guanaco does not have a dying place, it has a lot of characteristics sure to interest those who are lovers of natural history. Like the North American buffalo, it has wallowing places. On the plains of Patagonia, as on those of the Western States, great saucer-shaped hollows are seen in which the guanaco lies down to roll in the dust, but the Patagonian wallows are often much larger than any I ever saw in Kansas or Texas. The gauchos say this is because the guanacos resort to them in considerable herds--from thirty to one hundred--and at night sleep in them standing, heads out, in a ring, while the kids stand within the circle. This habit protects the young from the wild-cats and foxes. The guanaco has no effective defence against the assault of a panther save in flight. The old male guanaco with a herd of females to defend will fight when a panther attacks him unless the attack is immediately fatal. The canine teeth of the guanaco make a bad wound, and it can kick like a mule, but the panther is so quick and strong that the struggles of its victims are always hopeless. In the right season each tough old male gathers a harem of from thirty to fifty females, over which he presides in lordly fashion, and in one respect the old fellow is a very good head of a family. He leads the females into the hollows, where the grass is most abundant, while he remains on the highest knoll of the vicinity keeping watch for the enemy, and contenting himself by browsing on the scant herbage he finds about him. At times, however, the guanacos live in vast herds, and then all the older males remain on the higher knolls as sentinels. Their sense of smell is very keen. It is well-nigh impossible to get within half a mile of the sentinels by travelling down wind--some say they can smell a party of hunters that is a full mile away, and even more up wind. If approached carefully on the lee side one may get very close, however, and then the action of the sentinels is something that makes the gauchos laugh. The way the old bucks prance and jump stiff-legged and paw the air and neigh horse-fashion is one of the funniest things the plainsmen see. But, like the antelope, the guanaco is full of curiosity. With a little flag or even a handkerchief a man, after concealing himself on the lee side of a herd, can toll them within pistol range by simply waving the cloth in the air at brief intervals. It is likely that the animal distinguishes colors, for the use of two or three flags of bright but different colors excites them much more than one white flag will.