1. T. Kondo, S. Aoki, M. Ishiura, Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya, 464-01 Japan.
2. T. Mori, Department of Biology, Vanderbilt University, Nashville, TN, 37235, USA.
3. N. V. Lebedeva and S. S. Golden, Department of Biology, Texas A&M University, College Station, TX, 77843, USA.