The nests are built of stones, which the penguins gather often from a long distance, and they may be lined with a few stray quills and a bone or two. Every bird is an accomplished thief, and whenever possible steals stones from its neighbour's nest. There are usually two eggs. The first egg found by the Scotia naturalists was taken on October 29th; on October 31st no less than 739 eggs were gathered from the same rookery, and between November 2nd and 10th no less than 2,075 eggs were taken for domestic use. The period of incubation is about thirty-two days. Both the flesh and the eggs of this penguin form very nutritious and palatable food. Besides the black-throated penguin, it was estimated that there were at least 100,000 Gentoo penguins (Pygoscelis papua) in the Scotia Bay rookeries. The naturalists of the Scotia were fortunate in falling in with a great number of the Ringed penguin (Pygoscelis antarctica) at the South Orkneys at several rookeries, notably at Ellium Isle and Saddle Island. At a rookery on Mackenzie Peninsula there were about a quarter of a million of ringed penguins, and the rookery at Saddle Island was tenanted by about 50,000 birds. They were entirely absent during the winter, not reaching the South Orkneys till November 2nd. Over 1,000 eggs were taken by Dr. Pirie on December 12th,
