1. Department of Childhood Education, School of Education, Miyazaki International College, 1405 Kano, Kiyotake-cho, Miyazaki 889-1605, Japan
2. Department of Agriculture, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
3. Department of Biology, Aichi University of Education, 1 Hirosawa, Igaya-cho, Kariya, Aichi 448-8542, Japan