of animated beings. This shows how nicely the stimulus required to arouse hibernating animals is governed by the usual climate of the district, and not by the absolute heat. It is well known that within the tropics, the hibernation, or more properly æstivation, of animals, is determined, not by the temperature, but by the times of drought. Near Rio de Janeiro, I was at first surprised to observe, that, a few days after some little depressions had been filled with water, they were peopled by numerous full-grown shells and beetles, which must have been lying dormant. Humboldt has related the strange accident of a hovel having been erected over a spot where a young crocodile lay buried in the hardened mud. He adds, 'The Indians often find enormous boas, which they call Uji, or water serpents, in the same lethargic state. To reanimate. them, they must be irritated or wetted with water.'"

While waiting for the Beagle at Bahia Blanca, Darwin witnessed some of the incidents of a war which was then in progress with the natives. The troops of the famous South American dictator and general, Rosas, had declared war against the Indians, and proposed to exterminate them if possible. A report received, that a squad of men had been murdered, occasioned no little excitement, and as a result a troop of three hundred men came in from the Colorado. They were not Spaniards, as Darwin expected, but "tame Indians" of the tribe of the Cacique Bernantio, and they afforded him as interesting material for study and observation as so many wild beasts. They were wild, reckless, even brutal,

in the extreme. Many, crazed with intoxication, threw themselves upon the cattle slaughtered for them, and drank the streaming blood like so many brutes. The following day they started on the trail of the Indians, but the latter had made good their escape on the great pampas.

Darwin gives these Indians no little credit for skill and intelligence in obtaining results from what would be unintelligible to a white man. Thus they could examine the tracks of a thousand horses and tell how many were mounted by men, how many bore loads, whether they were fresh or fatigued, and whether they were going fast or slowly. For this they did not not need a fresh trail, one ten days old being read with equal ease. The Indians exhibited in their warfare a ferocity that would do credit to some of the red men of America. To show their nature, Darwin found that a man struck down seized his assailant by the thumb with his teeth and clung to it like a bull-dog while his eyes were torn out. Another feigned death, hoping an enemy might approach within reach of his knife, so that he might die red-handed. Another fled crying for mercy, and was seen trying to clear his bolas all the time. Darwin's informant nonchalantly said that he squared accounts with this fellow by striking him down with a sabre, then, dismounting, cut his throat with his knife a horrible picture, and seemingly impossible in a civilised land.

That the Indians are disappearing before the Spaniards, as they have in North America, is a wellknown fact, and their extermination is only a matter

Equestrian Skill of the Indians.

57

of time. Darwin learned that in 1535 there were villages which contained two or three thousand people, while at the time of his visit the remnants were wanderers upon the face of the earth.

To show the remarkable equestrian skill of these Indians, Darwin cites an incident of the escape of a chief. Pursued by the Spaniards and closely pressed, he sprang upon a fresh white horse, which had neither saddle nor bridle, drew his little son up behind him, and dashed away at full speed. When fired at he threw an arm about the horse's neck and fell to one side, and though the follower changed horses three times, the Indian made good his escape.

A Long Bullock Ride-Santa Fé-An Animal Collector-Large Fossils-Indian Superstitions-Darwin Ill-A Native Doctor— Geology-Gigantic Armoured Animals-Drought-The ParanaThe Jaguar-Darwin a Prisoner-Swimming Horses-Shower of Butterflies-Phosphorescence.

NE of the most interesting expeditions made by Darwin was from Buenos Ayres to Santa Fé, a distance of about three hundred miles. The conveniences for travelling were limited, the trip being made in bullock waggons -a tedious operation at best, but which had at least one commendable

feature: it afforded the naturalist ample opportunities to collect en route without the danger of being left behind should he stray from the road. This country was the home of the biscacha (Lagostomus trichodactylus), a little rodent somewhat resembling a rab