[M] Bison and wild cattle are grass eaters, and their natural habitats are the open plain and meadow regions. They also range into open forest lands where grasses can be found. The prehistoric 'urus' and 'wisent' of Europe were both found in forests, but this may not have been their natural habitat in Palæolithic times. See Appendix, Note IV.
[N] A recent article by A. Smith Woodward describes the fourth known specimen of Dryopithecus, lately discovered in northern Spain (see Woodward, 1914.2).
[O] There is a vast Pithecanthropus literature. That chiefly utilized in the present description includes Dubois,(13) Fischer,(14) Schwalbe,(15) Büchner.(16)
[P] In the Trinil skull as restored by McGregor (Fig. 36) the cranial capacity is 900 c.cm.
[Q] These horses are now identified respectively as E. mauerensis, E. mosbachensis, and E. süssenbornensis.
[R] This glaciation as it occurs in northern Europe has been termed Polandian by Geikie; in the Alps Penck has termed it the Riss; in America it is known as the Illinoian from the great drifts it deposited over the State of Illinois.
[S] This stage is known as the Helvetian or Dürntenian of Geikie; it is the Riss-Würm of Penck's terminology and the Sangamon of the American glaciologists.
[T] Modified after Schmidt.
[U] The weakness of Penck's argument for placing the Chellean in the Second Interglacial was exposed by precise observations of Boule(5) and Obermaier(6) in the Alps, the Jura, and the Pyrenees.
[V] The writer is indebted to M. Marcelin Boule and to M. l'Abbé Henri Breuil for their observations on this fauna and culture period.