In the year 1887 the Belgian geologists Fraipont and Lohest(36) discovered in a grotto near Spy, not far from Dinant on the Meuse, the remains of two individuals which are now distinguished as Spy I and Spy II. In the same stratum with the skeletons, beneath a layer of tufaceous limestone, flint implements of Mousterian age were embedded, together with remains of the woolly mammoth, woolly rhinoceros, cave-bear, and cave-hyæna. This discovery is one of the most important in the history of anthropology, because it definitely dated the Spy men as belonging to the period of Mousterian industry, and also because the authors immediately recognized these men as belonging to the race of Neanderthal and of Cannstatt, which at the time were supposed to be the same. Here for the first time the proportions of the cranium and the brain, the very primitive features of the lower jaw and of the teeth, the low stature, and several ape-like characters of the limb bones became known; here were observed the prominent supraorbital ridges of the Neanderthal type, the receding forehead, the cranial profile inferior to that of the lowest existing Australian races, the narrow, dolichocephalic skull. The limbs were found to have retained the anthropoid disproportion between the thigh-bone and the shin-bone, and the important discovery was made that this short, massively built, heavy-browed, dull-visaged Neanderthal man was unable to stand absolutely erect, the structure of the knee-joint being such that the knees were constantly slightly bent. In other words, the Spy man had not yet fully acquired the erect position of the lower limbs. [Illustration: FIG. 108. Skull known as Spy I, discovered in 1887, in front of the grotto of Spy, near Namur, Belgium. After Kraemer. One-quarter life size.] This discovery may be said to have established the Neanderthals in all their characters as a very distinct low race, but twenty-two years elapsed before this was further confirmed by the finding of another and still earlier type of Neanderthaloid at Krapina, in northern Croatia, Austria-Hungary, as described at the close of Chapter II (p. 181 above); a type which with its local variations was soon determined as unquestionably belonging in the same group with the man of Neanderthal and the men of Spy. Many years before, namely, in 1866, the Belgian anthropologist Dupont(38) had discovered the remains of another member of this race in a grotto on the bank of the River Lesse, near La Naulette, not far from Furfooz, in northern Belgium. This is now known as the La Naulette jaw and is found to be of Neanderthal type. It was associated with bones of the woolly mammoth, the rhinoceros, the reindeer, and a few fragments of other human bones.