n Some Stages in the Life History of Gnetum. By H. H. W. Pear- 
son, Sc.D., F.E.S., and Mary E. H. Thomson, B-A (With Plates 
XLV-L) 231 
The Theory of Automatic Eegulators. By H. Bohle . . . 271 
On Hybrid Forms in the Genus Satyrium, with Descriptions of 
Two New Forms. By A. V. Duthie. (With Plates LI-LIII) . 289 
Note on the Occurrence of Daphnin in the Arthrosolen. By M. 
EiNDL. (From the Chemical Laboratory of the Grey University 
College, Bloemfontein) 295 
African Myxomycetes. By A. V. Duthie ..... 297 
Ionization of Gases and the Absorption of Eontgen Eays. By Lewis 
Simons, B.Sc. (Lond. and Cape), Lecturer in Physics, Victoria 
College, Stellenbosch, South Africa . . . . . .311 
Note on Palmstr>z^m's Generalisation of Lamp's Equation. By Sir 
Thomas Mum, LL.D. 323 
