YUKON TERRITORY

2127

YUMAS

stamens are so placed that the pollen cannot get into the tube of the stigma without artificial aid. The plant is sterile without the moth, and the larvae of the latter feeds on the seeds, so that, in fertilizing the plant, the mother moth is providing for her offspring. The female moth (Pronuba yuc-casella) is about half an inch long and of silvery white color. She begins her operations after dark, and, in setting about to provide for the future generation, she first collects a pellet of pollen with her jaws and fore legs. She then begins to deposit eggs in the walls of the unripe fruit-pod, using her lance-like ovipositor to penetrate the outer covering. She then goes to the tube of the stigma, which leads into the fruit-pod and thrusts pollen down it, using her tongue to push the pollen toward the undeveloped seeds. The larvae are hatched and feed upon the developing seeds, but as not all of these are consumed, the double purpose has been effected of fertilizing the plant and providing food for her young. Consult The Yucca Moth and Yucca Pollination, Missouri Botanical Garden Report for 1892.

Yukon (yoo'kon) Territory, Can., the most important part of northern Canada at present. It extends from the northern boundary of British Columbia to the Arctic Ocean and from the Rocky Mountains to Alaska, U. S. A. It is about 650 miles from north to south by 550 in greatest breadth from east to west. Although it does not touch the Pacific, its southern boundary is only 30 miles from tidewater. A railway of no miles connects at Skag-way, the head of tidewater in Alaska, with White Horse at the head of steamboat navigation on Yukon River. This is navigable for large steamers from White Horse through Yukon Territory and Alaska to Bering Sea, a distance of 1,630 miles.

Yukon is important because of the gold discoveries on Klondike River in 1897. There had been gold-mining on a small scale on Stewart and Forty Mile Rivers, but in 1897 remarkably rich discoveries were made in two streams flowing into the Klondike, a tributary of the Yukon, and in some adjacent streams. The stampede which followed was one of the most remarkable the world has known. Since that time over $100,000,000 in gold have been taken out, and investments of many millions are now being made in the expectation of taking out one hundred million dollars more in the next few years. There are placer-mines in active operation in widely separated portions of the territory, and silver, copper, quartz and coal mines as well. Dawson, the capital, is on the Yukon at the mouth of the Klondike. Although Yukon is only a few miles south of the Arctic circle, the climate in summer is very pleasant, and hardy vegetables, as turnips and cabbages grow very well. Below the surface the ground in the northern part of the territory is always frozen, but the surface is not frozen from April to October inclusive. Population 8,000.

Yukon, a river rising in the Dominion of Canada and flowing through Alaska into the Pacific at Norton Sound, its total length being about 2,000 miles.

Yu'ma, the southwestern county of Arizona, U. S. A., lying directly north of Mexico. It is intersected by Gila River and is separated from California by the Colorado. The valleys, when irrigated, are fertile, but the rest is desert. Yuma, the county-seat, with 1,402 inhabitants, stands on the eastern bank of Colorado River. See Arizona.

Yumas, a tribe of American Indians, very few in number, occupying the territory on both sides of the Colorado near its junction with the Gila.