184 TJie A?nerica?i Geologist. Soptombor, is99 
drift, first recognized and named by Dr. G. ]\I. Dawson in the province 
of Alberta, belongs doubtless to the stage of general accumulation of 
the ice-sheet, followed by some recession, and then by the maximum 
glaciation known as the Kansan stage. Accompanying the retreat of 
the ice-sheet from this greatest extension west of the Wisconsin 
driftless area, an advance appears to have taken place east and south 
of that area, the ice-sheet then reaching its outermost boundary in 
Illinois, with encroachment on a part of the east edge of Iowa. Under 
this view, the Albertan, Kansan, and Illinoian stages of glaciation, fluc- 
tuating on the borders of the drift region, were probably, as geologists 
reckon time relations, closely consecutive. Next ensued a long inter- 
glacial stage, when the ice boundary retired so far northward as to 
uncover all of Iowa and the southern half of Minnesota, during prob- 
ably 15,000 years, more or less, as Prof. N. H. Winchell has argued 
from changes of the course of the Mississippi river at Minneapolis. 
Afferward the greater part of the relinquished ground, reaching south 
to a maximum limit in the vicinity of Des Moines, was again enveloped 
by snow and ice. To this glaciation belong the lowan and Wisconsin 
stages, again closely consecutive, the former characterized by abundant 
loess deposition, and the latter by the formation of prominent mar- 
ginal moraines. w. u. 
Geology of Southwest Missouri : Report on Greene County. By 
Edward M. Shepard. (Missouri Geological Survey, Charles R. Keyes, 
State Geologist, Vol. XII, pt. i, Jefferson City, 1899.) 
While nominally limited to a single county, so much related matter 
from other parts of southwest Missouri is brought in, that the Greene 
county report becomes in reality a key to the geology to all that portion 
of the state. Aside from its intrinsic value as a repository of local geo- 
logical facts the account is especially valuable for two other reasons. In 
the first place it is intended to serve as a handbook of local geology for 
the geological students of Drury college at Springfield, and the prepara- 
tion of the report has had this feature constantly in mind. Professor 
Shepard's 20 years connection with the institution, and his long experi- 
ence as a mining expert and geologist for southwest Missouri has made 
this phase of the report such as could not be expected to be attained in 
any other way. In the second place the Greene county report is the first 
to appear of a series of similar reports that were planned and nearly 
completed by the late geological survey of Missouri under the director- 
ship of Dr. Charles R. Keyes. Professor Shepard's report is then the only 
official document of any scientific merit, and value to mining men and 
geologists that is likely to appear for a long time to come. 
Greene county lies upon the crest of the great Ozark dome. In this con- 
nection the origin of the name is not without interest. Quoting Feather- 
stonhaugh it is stated that "It was the custom of the French Canadians to 
abbreviate their names. If they were going to the Arkansas mountains 
they would say that they were going 'Aux Arcs', and thus these high- 
lands have obtained the name Ozarks from American travelers. Spring- 
field the chief city of southwest Missouri is exactly on the drainage di- 
