1. Dep. of Earth Sciences; Memorial Univ. of Newfoundland; St. John's Newfoundland A1B 3X5
2. Dep. of Renewable Resources; Macdonald College of McGill Univ.; 21111 Lakeshore Road Ste. Anne de Bellevue Quebec H9X 3V9 Canada
3. Dep. of Biochemistry; Memorial Univ. of Newfoundland; St. John's A1B 3X9 Canada