The greatest generalization of this second period, however, was that partly prepared for by d'Orbigny, as will be more fully explained later in this article, and clearly expressed by Agassiz - namely, the law of repetition of ancestral stages of life in the course of the successive stages of individual development.
The very flat and rich prairie near Winnipeg is the former bed of the glacial Lake Agassiz; but most of the prairie to the west is of a gently rolling character and there are two rather abrupt breaks in the plain, the most westerly one receiving the name of the Missouri Coteau.
His attention was directed to the question of the flow of glaciers in 1840 when he met Louis Agassiz at the Glasgow meeting of the British Association, and in subsequent years he made several visits to Switzerland and also to Norway for the purpose of obtaining accurate data.
Agassiz (in his work on Lake Superior) tells us that the roadside weeds of the north-eastern United States, to the number of 130 species, are all European, the native weeds having disappeared westwards; while in New Zealand there are, according to T.
See Rodolpho Theophilo, Historia da Secca do Ceara, 1877 a 1880 (Fortaleza, 1883); Professor and Mrs Louis Agassiz, A Journey in Brazil (Boston, 1869); George Gardiner, Travels in the Interior of Brazil (London, 1846); C. F.