1889.] Orio-iii of the Loess. 791 
the top of their holes. The crawfish is a queer citizen. I can't 
understand him. I fail to see where he puts all the dirt that must 
come out of his hole. Last year 1 poured about a bushel of dry- 
sand into one of his holes where many others were duj; near by 
without filling it ; yet the mud balls he had stacked up about the 
hole would not have filled my hat crown. 
The ants too are known to bring a considerable quantity of 
earth from beneath to the surface in building their hills. Only a 
i^w days ago I was surveying in a five-acre cow pasture at Rose- 
dale, a village in the south part of this county, and there I 
noticed that wherever the excrement of the cow was dropped, a 
bug which lays its eggs in a ball of the excrement and buries it in 
the ground, had carried up great quantities of fine earth from the 
excavations below. At a very recent one there was fully a gallon 
of fine earth piled up on the ground. This was on the second or 
terrace bottom of Raccoon creek, and over a gravelly subsoil. 
On the insect hypothesis, there would of course be a limit to 
the thickness of each surface formation. Insects will dig no 
deeper than will scr\e their necessities. I have no reason to sup- 
pose they u (xild go deeper than three feet ; but I have often seen 
the yellow clay ten to twelve feet thick on the iiigh ridges. This 
would require a deep digging insect, or else an accumulation from 
some source above the surface. The crawfish would dig deep 
enough, but he leaves the field when it becomes high and dry. 
Besides this, if the fine material had been taken out of the top of 
the glacial, gravelly cla\-. it would havt> left a stratum of clean 
gravel as far down as the fine material had been thus extracted, 
which we do not find to be the case here. 
I notice in the second or terrace bottoms along the Wabash 
river in this vicinity a coat of fine sandy loam on top of the orig- 
inal gravel and sand, which latter was left by the Wabash when it 
carried ten thousand times as much water as it now does. There 
has never been any slack water over these terrace bottoms since 
the Wabash which made them dropped into its present limits. I 
shall some time tr>^ to prove what I here merely assert, to-wit : 
That the ancient water supply of the Wabash was suddenly cut 
off, and there was one last great flood, which left its natural 
