For these and other reasons Hrdlička,(77) who has recently made a broad comparative study of the chief Neanderthal remains of Europe, is of the opinion that the Neanderthals partly evolved into the lower races of _Homo sapiens_; being not only in some measure ancestral to such very primitive forms as the Brünn or Předmost race of Upper Palæolithic times, but even contributing to the higher race of the Crô-Magnons. He also holds that traces of Neanderthal blood and physiognomy are not lacking even among modern Europeans. A contrary view is set forth in the present volume; namely, that the Neanderthals represent a side branch of the human race which became wholly extinct in western Europe. This view the author shares with Boule and with Schwalbe. Certainly the evidence afforded by the known Upper Palæolithic burial sites does not support the theory that the Neanderthals persisted. It is possible, however, that the Upper Palæolithic skeletons discovered at Předmost, and now awaiting description by Maška, may modify this conclusion and demonstrate Hrdlička's theory that the Neanderthals survived and left descendants or men of mixed Neanderthal and _Homo sapiens_ race along the valley of the Danube. Whatever may have been their fate in other regions, certainly the most sudden racial change which we know of in the whole prehistory of western Europe is the disappearance of the Neanderthal race at the close of the Mousterian culture stage, which was the latest industrial period of Lower Palæolithic times, and their replacement by the Crô-Magnon race. From geologic evidence the date of this replacement is believed to have been between 20,000 and 25,000 years before our era. So far as we know at present, the Neanderthals were entirely eliminated; no trace of the survival of the pure Neanderthal type has been found in any of the Upper Palæolithic burial sites; nor have the alleged instances of the survival of the Neanderthal strain or of people bearing the Neanderthal cranial characters been substantiated. We incline to agree with Boule and Schwalbe that the supposed cases among modern races of the transmission of Neanderthal characters are simply low or reversional types, which, upon close analysis, are never found to present the highly distinctive and peculiar combination of Neanderthal characteristics.