Abstract
We discussed about habitation of the pond frog Rana porosa porosa, and correspondence of the structure of a ditch in the side of a paddy field in the Isawa alluvial fan. As the result of count census on a levee, the density of this frog was high in ditches of a ground material, and remarkably low in ditches of the concrete material. And density of this frog was the highest in the ditch, which had the moderate biomass of grass on a levee. It was guessed that two points had operated to plus on an abundance of this frog. The points were that there are a great many ditch of ground material, and the |and consolidation paddy field of old time is maintained in this area.
