ERRATA Vol. 63,1966 Page 157 line 8*. For (structure XX . . read (structure 20. . Page 158 line 21. For analogous to XX read analogous to 20. Page 159 line 16. For R,CoF read R,COF. Page 160 line 16. For R,S or R,Ge have been interpreted read R,Si or R,Ge have been interpreted2''. Page 172 line 9*. For (P,O,F)-read (P,0,F)4-. line 8*. For FPO,-read FP0,2-. Page 173. Delete reference below formula. Page 176 line 23. For SbF40S0,F read SbF,SO,F. Page 188 Ref. 32. For M. N. Bucklish read M. N. Bukhsh. Page 346 line 4. For a-lithio-organoalkane read a-lithio-organoalane. Page 426 line 9. For opposite read same. Page 426 line 21. For cyclobutanes read cyclobutenes. Page 427 Footnote. For tetracyclone read cyclones. Page 432. The equilibrium sign between (71) and (74) should be in square brackets.Page 432 Formula (75). Insert Me at C-5. Page 434 line 12*. For H, 't 7-0read H z 8.0. Page 507 Ref. 53. Add Katsumi Kotera and Yuzo Nakagawa. Page 529 bottom line. For chained read chain. Page 530 line 9. For have been reported to read have been reported of. Page 532 line 12. For diastereoisomers were read diastereoisomers are. line 17. For asopressin read vasopressin. Page 595 line lo*. For Studies on Other a-Glugans read Studies on Other CX-GIUCIUIS. Page 643. Transfer formula to page 646. Page 646. Transfer formula to page 643. Page 745 Ref. 420. The C-C bond length in the C ring is 1.37 and not 1.73. Page 761. Ref. 563. For M. Sundaralingam read M. Sunderalingam. Page 761 line 22. The angle between the base and the ribose is displaced by more than 0.5 A from the plane of the remaining ring atoms and on the same side as C(5) shouZd read The angle between the base and the ribose planes is 55,. C(3') of the ribose is displaced by more than 05 A from the plane of the remaining ring atoms and on the same side as C(5'). Page 803. Add Nakagawa Y. 507. * From foot of main text.