Reviews—Glacial Geology of North America. 281 
Bellerophon, Patellostium, Bucanopsis, Euphemus, Euomphalus, Nati- 
copsis, Platyceras, Strophostylus, Loxzonema. Cephalopoda: Ortho- 
ceras, Protocycloceras, Solenocheilus, Goniatites, Gastrioceras, Adelpho- 
ceras, Aptychus. Trilobita: Griffithides. Ostracoda: Puraparchites, 
Primitia, Glyptopleura, Cytherelila. 
Exception must be taken to two of the above generic determinations. 
The shell figured and described as Pleurotomaria arkansana might 
more accurately be referred to Murchisonia, while Pleurotomaria aff. 
perhumerosa in all probability belongs to Scalites of Emmons as 
interpreted by De Koninck and other paleontologists of Europe, 
which according to Eastman (Zittel’s Text-book of Paleontology, 1918, 
p- 527) should be grouped in the Raphistomide of Ulrich and 
Scofield, a family with Euomphaloid and Pleurotomaroid affinities. 
Ree BON: 
V.—Guacrat Groroey or Nort America. 
PONDEROUS but interesting tome of 529 quarto pages, The 
Pleistocene of Indiana and Michigan, and the History of the Great 
Lakes, by F. Leverett and F. B. Taylor, forms Monograph 53 of the 
United States Geological Survey. It describes the glacial features of 
a district lying between the areas covered by the previous Monographs 
Nos. 38 and 41, and presents the latest and most detailed account 
of the vicissitudes of the immense glacial lakes whose shrunken 
remnants form even now the greatest system of fresh-water lakes in 
the world. Four great ice-advances from different directions are now 
recognized, with three well-marked interglacial stages, and many 
minor advances and retreats occurred within each stage. Each has 
left easily traceable topographic effects or deposits; but it is the last, 
or Wisconsin, stage of glaciation, whose deposits cover practically all 
the rest, which has modelled the present relief and drainage of the 
vast area surrounding the Great Lakes. The fluctuations of the ice 
border have left well-marked morainic systems, each of which is traced 
‘across country and fully described in the memoir. 
The basins of the Great Lakes were once valleys with free drainage 
but no lakes. The drainage was obstructed by the ice-sheet in the 
way with which we are now familiar, thus initiating enormous lakes, 
‘the levels and margins of which fluctuated with the movements of 
the ice. Fortunately they left excellent beaches and unquestionable 
overflow channels, whereby their former extent and respective outlets 
have been easily determined. The broad lines of this history are now 
well known, but with every addition of new facts there is a sensible 
modification of their details. It has been found especially that the 
succession of changes involved in the later lake history is much more 
complex than formerly supposed. This monograph is printed and 
published regardless of expense, with a beauty and wealth of 
illustration that we can only sigh for on this side of the Atlantic. 
GW ok: 
VI. Bortnes in tHe Terrrarres oF Vicrorta, Austratta.—The 
‘“Cainozoic Geology of the Mallee and other Victorian Bores’”’ 
(Records Geol. Surv. Victoria, iii (4), 1916, pp. 327-430, pls. Lxiii— 
Ixxvill, price 1s. 6d.), by Frederick Chapman, is a report we have 
