336 The American Naturalist. [April, 
probable that, since the alternation in the tarsus in that family is un- 
doubted, it will also be found to exist in the carpus, as required for the 
missing type. Should this prove to be the case, the Periptychide must 
be removed from the order Condylarthra to the Amblypoda, where it 
will form the second family of the suborder Taligrada, the other family 
being the Pantolambdide. The two families will differ in this, that in 
the Periptychide the molars are bunodont, while in the Pantolambdide 
they are primitively selenodont, or with V-shaped cusps. This arrange- 
ment, if correct, puts the Periptychide in direct ancestral relationship 
to the Diplarthra, and so far confirms Schlosser’s hypothesis that that 
family is the ancestor of the Artiodactyla. This view is also in ac- 
cordance with that expressed by Osborn and Earle in their important 
paper on the Fossil Mammals of the Puerco: Bull. Am. Mus. Nat. 
Hist. New York, 1895, p. 47. 
The families of the Condylarthra will be, in that case, the Phena- 
codontide and the Menscotheriide, and the Pleuraspidotheriide of 
Lemoine, if the last be different as a family from both of the others. 
—E. D. Core. 
Glacial Beaches of Michigan.—During the past year Mr. F. 
B. Taylor has made a study of the moraines, abandoned beaches and 
outlets of the glacial lakes which formerly occupied the southern part 
of the lower peninsula of Michigan. His conclusions are as follows : 
The glacial waters that gathered in the Erie, Huron and Ontario 
basins during the retreat of the ice-sheet underwent many changes. In 
falling from their highest level to the present level of Lake Erie the 
Stages. Lakes. Beaches. Outlets. Moraines. 
1 |Maumee Van Wert.......... Fort Wayne........| Defiance. 
2 \Onnamed a Leipsic. Imlay Toledo and De- 
: troit. 
3 | Whittlesay Belmore. Tyre Ubly. ......... Port Huron, Sagi- 
naw. 
4 /|Unnamed Arkona Undecided Undecided 
5 Warren Forest Pewamo. Undecided 
(Bull. Geol. Soc. Amer., Vol. 8, 1897). | 
glacial waters changed the place of their outlet four or five times. At 
each change they paused for a time, sufficient to make a distinct beach. 
For the whole series of lakes the author would propose a descriptive, 
