The dating equipment in the Palaeoecology Laboratory remains essentially as described in R., 1970, v. 12, p. 285–290, and the operating conditions as described in R., 1970, v. 12, p. 291–297. Small samples, however, have been counted at a filling pressure equivalent to 152 cm Hg at 20°C. Charcoal samples pretreated by nitration have been treated as described in R., 1970, v. 12, p. 285–290. Other charcoal samples have been pretreated using the following technique developed by P. Q. Dresser: samples are washed in 5% sodium hydroxide; this is followed by treatment in a solution composed of 8% potassium permanganate and 10% sulphuric acid, at 80°C for 20 mins, to remove residual rootlets and organic matter. Unless specifically stated, the samples have been collected by the authors and other members of the Laboratory: M. G. L. Baillie, P. Q. Dresser, Adelaide Goddard, and I. Goddard. Where a sample has been collected for a specific research project the collector's initials are given. Routine operation of the dating apparatus has been carried out by Mrs. Marilyn Carse and Mrs. Florence Qua to whom we are much indebted.