Ecology of the Cincinnati Region 
195 
True aquatics are scarce or entirely absent, but the amphibious plants 
are numerous. These are seldom arranged in distinct zones, as these 
flood plain ponds are often very irregular in outline. Cat-tail (Typha 
latifolia), arrow-head (Sagittaria latifolia), and bulrush (Scirpus validus) 
usually occupy the margin of the pond, or are scattered through it in 
patches. Each wetter spot in the general swampy area is occupied by 
Fig. 50. Ponds on the Ohio-Little Miami flood plain. 
these plants, and the intervening spaces are filled with other amphibious 
plants, among which are Alisma Plantago-aquatica, Cicuta maculata, Pen- 
thorum sedoides, Ludvigia alternifolia, L. palustris, Rumex altissimus, 
and Asclepias incarnata. Here and there are patches of the buttonbush 
(Cephalanthus occidentalis), and advancing upon the herbaceous plants 
of the pond and its swampy margins are willows and cottonwoods, or 
sedges and grasses. Fig. 50 is a view of a flood plain swamp, in which 
are a number of small stretches of open water. 
