[Illustration: FIG. 106. Section of that part of the valley of the Düssel known as the Neanderthal, showing the location of the limestone grotto where the Neanderthal skeleton was discovered. Drawn by C. A. Reeds.] Sera(27) considers the Gibraltar skull to be the most ape-like of all human fossils and thinks it should not be classed with the Neanderthaloids at all, but should be regarded as Pre-Neanderthaloid; this view is shared by Keith. Boule, however, believes that this skull is of the same geologic age as that of Spy, La Chapelle, La Ferrassie, and La Quina; everything leads us to believe,(28) he remarks, that the skull of Gibraltar is a female skull of Neanderthal type. He elsewhere refers to the skulls of Gibraltar, of La Quina, and of La Ferrassie II as probably those of female Neanderthals. [Illustration: FIG. 107. The original type skull of Neanderthal (left side) discovered in 1856. After Schwalbe. One-quarter life size.] The type skull of this great extinct race of men is that of Neanderthal--certainly the most famous and the most disputed of all anthropologic remains--appreciated by Lyell and Huxley, but passed over by Darwin, and finally established by Schwalbe as the most important missing link between the existing species of man (_Homo sapiens_) and the anthropoid apes. In 1856(29) some workmen were engaged in clearing a small loam-covered cave about six feet in height, the so-called Feldhofner Grotto, in the cretaceous limestone of the valley known as the Neanderthal, on the small stream Düssel flowing between Elberfeld and Düsseldorf. They discovered some human bones, probably a complete skeleton representing an interment, which, unfortunately, were allowed to be scattered and crushed. Doctor Fuhlrott rescued the parts that remained, including the now famous skullcap, both thigh-bones, the right upper-arm bone, portions of the lower arm, bones of both sides, the right collar-bone, and fragments of the pelvis, shoulder-blade, and ribs. All the bones were perfectly preserved and are now to be found in the provincial museum of Bonn. The discovery made a great sensation, but at first the age of these fossils remained doubtful; some 150 paces from the grotto, in a similar small cave were found bones of the cave-bear and rhinoceros. In 1858 Schaaffhausen's memoir(30) appeared, in which he gave the first detailed description of these remains as belonging to a primitive original race differing in every point from recent man, and he never wavered from this standpoint. In 1863(31) Busk, Huxley, and Lyell also placed this skeleton in its true intermediate position between man and the anthropoid apes. The determined opinion of Virchow that this was not a normal type of man exerted so great an influence that not until the classic work of Schwalbe,(32) between 1899 and 1901, did this skeleton assume its commanding importance for all time, and even this was subsequent to the discovery of two other Neanderthaloid races.