Megalonyx-heds in Kansas. — Udden. 
343 
3) Spherium striatum Lam. 4) Spherium sulcatum Lam. 
5) Pisidium abditum Haldeman. .6) Anodonta, sp. 
7) Valvata tricarinata Say. 8) Gammarus, sp. 
The top of the gravel changes into sand and this by transitions 
becomes clay. At first this clay is mixed with coarser material, 
but this disappears above, where it is entirely homogeneous. At 
one place it is very fine and has a jointed structure. The joints 
show beautiful dendritic impressions of manganese oxide. At 
another place it is coarser, the jointed structure is absent, and the 
manganese (?) is seen only as distant blotches. As far as known 
the thickness of the clay does not exceed four feet. 
Resting on the clay and separated from it by a well defined line 
of contact, there is a stratum of volcanic dust which has been 
The dotted part represents the area over which the Pleistocene is at least 75 
feet deep. The representation of the Cretaceous is from memory. 
identified at six places that run in a line across the trough on the 
north slope of the watershed. The altitudes of these exposures 
range from 1430 to 1480 feet above the sea level. In the outcrop 
occupying the lowest level, the material is well assorted, the fine 
and the coarse grains being separated into intermingled, but dis- 
tinct, thin layers. It has here settled through a considerable 
depth of water. At another place where it occupies a position 
about 40 feet higher, the particles are not assorted, the bed rests 
on a thin black seam containing bog-manganese and bog-iron, and 
underneath the jointed clay is dark and carbonaceous. This sug- 
fche Proceedings of the Phil. Ac. of Nat. Sciences. The specimen was 
figured in the August number of the American Naturalist lor 1890. 
