Revieir of Recent Geological Literature. 353 
patina, found on the plateaus of the chalk and other districts in beds 
unconnected with the present valley drainage. 3. Paleolithic, repre- 
sented by coarsely flaked implements from the higher river drift of the 
present valleys, and by others of similar forms found in the oldest brec- 
cia deposit of limestone caves. 3. Mesolithic, characterized by more 
skillfully flaked implements, which appear, by their forms and often by 
the deposits containing them, to be intermediate and transitional, bridg- 
ing the interval from the preceding to the next stage. 4. Neolithic, 
with implements of polished or delicately flaked stone. In the north- 
ern parts of Great Britain, and in Denmark and Scandinavia,comprising 
the countries covered by the European ice-sheet, the only traces of 
stone-working prehistoric men belong to this latest neolithic stage, 
showing, as was pointed out many years ago by Prof. James Geikie, that 
the more ancient stages of human progress in Europe were past before 
the end of the Ice age. 
An Introduction to the Study of Mommals, Llv'uig (tad Extinct. Br 
William Henry Flower, Director of the Natural History Department, 
British Museum, and Richard Lvdekker. London, 1891, pp. xvi, 
763, with 357 figures in the text. This is a well arranged, interestingly 
written, and finely illustrated volume, indispensable to the zoologist and 
scarcely less to the geologist and paleontologist,since it notes under each 
genus its representation, if any,by fossil species, while for many of the 
orders their probable phylogeny or evolution is traced. Of the Simiidte 
or true anthropoid apes of the eastern hemisphere, which structurally 
and in intelligence make the nearest approach to man, the earliest and 
only fossil species known is the extinct Dryopithecus of the Middle Mio- 
cene in France, pronounced by Gaudry to be the most generalized mem- 
ber of the family. The senior author's investigationsof the varieties of 
the human species refer them to three types: 1. Ethiopian, Negroid, or 
Melanian, black. 2. Mongolian, or Xanthous, yellow or brownish. 3. 
Caucasian (a "misleading" terra), white, but in some branches quite 
black. The aboriginal American peoples are regarded as a division un- 
der the Mongolian type, and ihe Malayan, Papuan, Australian, and 
Maori races are attributed to intermingling of the three types, chiefly of 
the first and second. The poverty of our geologic record is impressively 
exemplified by the entire lack of "evidence of the anatomical characters 
of man as he lived on the earth during the time when the most striking 
racial characteristics were being developed during the long ante-historic 
period in which the Negro, the Mongolian, and the Caucasian were be- 
ing gradually fashioned into their respective types." Among the higher 
Anthropoidea man alone has been able to migrate to the western hemi- 
sphere from his place of origin, which was doubtless with the Simiidae in 
the tropical zone of the Old World. His migration was apparently at a 
h'gh northern latitude, where the severity of the climato debarred the 
passage of the apes and may very probably have made that of men im- 
possible until after they attained the art of making warm clothing. The 
antiquity of our race in America, however, shown by geologic discover- 
ies of stone implements, is accepted as almost equal with that yet proved 
for men in the old world, extending bade in each hemisphere to the 
