2 10 
The Ohio Naturalist. 
[Vol. XI, No. 1 
Hibiscus zone is coming in. Twenty feet east of the western 
margin of the belt the marsh zones are interrupted by a boat-house 
on the beach with a runway for boats extending into deeper 
water. The development of the marsh formations on the north 
side has thus been interfered with; and the margin is also more 
exposed to storm winds and waves. A sandy beach 60 feet wide 
is building; it is occupied in part by the Polygonum-Scirpus and 
in part by the Scirpus lacustris zone. 
At the south end of the section studied both lateral zonation 
and layering (etagen) are strikingly shown. There is a marked 
increase in elevation from one lateral zone to another, from the 
floating Nelumbo leaves to the tall Ulmus amcricana and Quercus 
palustris. This is well shown in the photographs. There is a 
poor development of etagen in the individual associations. In 
some there are the dominant plants and then the ground cover, in 
others a weak irregular growth of taller herbs, while in the forest 
the shrubs have either been cut or are young plants, and the vines 
generally trail over the ground. 
I wish to take this opportunity of expressing my appreciation 
of and thanks for the favors shown me by Dr. Alfred Dachnowski, 
under whose supervision the survey was made, to Mr. Lionel King 
for the two excellent photographs and to Mr. Booton and Mr. 
Sawyer of the State Canal Commission for the map and informa- 
tion concerning the acreage and history of Orchard Island. 
AN OPEN VALLEY NEAR HARRISBURG, OHIO.* 
R. H. Nichols, 
The subject under investigation is an open valley near Harris- 
burg, Ohio, on the B. & 0. Railroad about fifteen miles southwest 
from Columbus. This valley at one end joins Big Darby valley 
near Harrisburg; at the other end after a circuitous course of 
about three miles on the west side of the creek it again joins 
Big Darby. 
About a mile from the north end the water parts at present on 
a divide (see map) consisting of two small alluvial fans. The 
topographic map shows a small stream entering the valley at the 
divide from the west and flowing northward through the valley, 
but today this stream is buried in a tile drain and no stream nor 
channel can be found in this part except a very short one at the 
end of the valley. 
* This paper covers a field problem worked out as a part of the course in 
Advanced Physiography given by Dr. George D. Hubbard at Ohio State 
University. 
