This group, which is very remarkable for several reasons, was discovered in 1770 by a fur-hunter named Liakhov. He had seen a great herd of reindeer coming south over the ice, and rightly concluded that there was land to the northward. This led to his discovery of Liakhov and Maloi Islands and in 1773 of Kotelnoi Island. Faddiev and Belkova Islands were discovered in 1805, New Siberia in 1806, and Bennett Island in 1881. With the exception of a few granite hills, practically the whole soil of Liakhov Island was found to consist of mammoth bones. Kotelnoi is composed of strata of the Devonian period and Silurian coral. But New Siberia with its “Hills of Wood” is the most curious island of all. On its northern coast there are lofty and precipitous rocks of sandstone. The “wood hills,” 210 feet high, are formed of horizontal sandstone strata alternating with bituminous trunks of trees. On the summit there are long rows of tree-trunks fixed perpendicularly into the rock, and projecting 7 to 10 inches. The “wood hills” extend for more than three miles along the coast. The largest trunk is 10 inches in diameter, the wood is friable, black with a slight gloss, and not very hard. The mammoth ivory from Liakhov Island soon became a source of commercial profit; indeed, the quantity that was carried off by Liakhov and his successors was enormous. In 1821 a merchant brought back 20,000 lb. of ivory, each mammoth tusk averaging a weight of 108 lb. In 1809 Sannikoff collected 10,000 lb. of ivory. The supply continued, and in 1856 and 1857 great boats are mentioned in the river Lena, laden with fossil ivory. At Yakutsk, from 1825 to 1831, the sale of ivory amounted to 54,000 lb. annually, besides 5700 lb. sold in other markets. Middendorf’s calculation was that the annual sales amounted to 110,000 lb., representing 1000 individual mammoths. A very large proportion of this ivory comes from Liakhov Island, and there appears to be no diminution in the supply. There is also believed to be a vast additional store on the sea bottom, as tusks are found in abundance when the sea recedes after a long continuance of easterly winds. Sannikoff saw land to the north of the New Siberian Islands, but was prevented from reaching it owing to open water. This was the Bennett Island, discovered by De Long in 1881, in 76° 38′ N. and 148° E. He explored 17 miles of the south coast of the island, and found great numbers of birds breeding on the cliffs. Here also mammoth tusks were met with. A barren rocky ice-capped islet, named Jeannette Island, was also discovered by him, and another named Henrietta Island, 27 miles away. Hedenström, a Russian officer residing at Yakutsk, was employed by the Government to survey the New Siberian Islands in 1809, accompanied by Sannikoff, and he was occupied on this service for three years.